Dose-dependent suppression of serum prolactin by cabergoline in hyperprolactinaemia: a placebo controlled, double blind, multicentre study. European Multicentre Cabergoline Dose-finding Study Group

Consensus guideline for the diagnosis and management of pituitary adenomas in childhood and adolescence: Part 2, specific diseases

Pituitary adenomas are rare in children and young people under the age of 19 (hereafter referred to as CYP) but they pose some different diagnostic and management challenges in this age group than in adults. These rare neoplasms can disrupt maturational, visual, intellectual and developmental processes and, in CYP, they tend to have more occult presentation, aggressive behaviour and are more likely to have a genetic basis than in adults. Through standardized AGREE II methodology, literature review and Delphi consensus, a multidisciplinary expert group developed 74 pragmatic management recommendations aimed at optimizing care for CYP in the first-ever comprehensive consensus guideline to cover the care of CYP with pituitary adenoma. Part 2 of this consensus guideline details 57 recommendations for paediatric patients with prolactinomas, Cushing disease, growth hormone excess causing gigantism and acromegaly, clinically non-functioning adenomas, and the rare TSHomas. Compared with adult patients with pituitary adenomas, we highlight that, in the CYP group, there is a greater proportion of functioning tumours, including macroprolactinomas, greater likelihood of underlying genetic disease, more corticotrophinomas in boys aged under 10 years than in girls and difficulty of peri-pubertal diagnosis of growth hormone excess. Collaboration with pituitary specialists caring for adult patients, as part of commissioned and centralized multidisciplinary teams, is key for optimizing management, transition and lifelong care and facilitates the collection of health-related quality of survival outcomes of novel medical, surgical and radiotherapeutic treatments, which are currently largely missing.

The use of hormone stimulation in male infertility

Infertility affects 15% of couples worldwide and in approximately 50% of cases the cause is secondary to an abnormality of the sperm. However, treatment options for male infertility are limited and empirical use of hormone stimulation has been utilised. We review the contemporary data regarding the application of hormone stimulation to treat male infertility. There is strong evidence supporting the use of hormone stimulation in hypogonadotropic hypogonadism but there is inadequate evidence for all other indications.

Recurrent Priapism From Cabergoline and Bromocriptine in a Hypogonadal Man With Prolactinoma

Dopamine agonists are generally well tolerated and represent the first-line therapy for prolactinomas. We report a case of a 20-year-old man with a macroprolactinoma who developed recurrent priapism with cabergoline and bromocriptine. Transsphenoidal pituitary adenoma resection was done with normalization of the prolactin level. Priapism is a rare side effect of dopamine agonists that warrants discontinuation of therapy. Patients should be educated about this potential side effect at the time of prescribing the medication.

Efficacy and safety in the treatment of hyperprolactinemia: A systematic review and network meta-analysis

WHAT IS KNOWN AND OBJECTIVE

Hyperprolactinemia is a neuroendocrine disease that is responsible for a quarter of cases of secondary amenorrhea, which can lead to infertility in women. Dopaminergic agonists (bromocriptine, cabergoline, quinagolide) can be used in the treatment. However, there is a lack of secondary studies that compare their efficacy and safety, especially through a network meta-analysis. Thus, to contribute to the decision-making, a systematic review and network meta-analyses (NMA) were performed to evaluate the efficacy and safety of dopaminergic agonists in the treatment of hyperprolactinemia.

METHODS

Randomized clinical trials (RCT) were retrieved through PubMed, Web of Science and Scopus databases. The efficacy and safety of the drugs were compared, considering the following outcomes: prolactin (PRL) levels, number of patients with galactorrhoea, menstrual irregularities and adverse drug reactions. NMA was built for each outcome. Results were reported as odds ratios (OR) with 95% credibility intervals. Ranking probabilities were calculated by surface under the cumulative ranking analysis (SUCRA) and Stochastic multicriteria acceptability analysis (SMAA).

RESULTS AND DISCUSSION

Seventeen RCTs were included in the systematic review and fifteen in the meta-analyses. The drugs had similar efficacy, considering the PRL levels. The SUCRA analysis showed that quinagolide (0.075 and 0.05 mg/day) was superior for reducing irregular menstruation, whereas bromocriptine was the best (97%) for galactorrhoea. Cabergoline proved to be the safest drug, except for abdominal pain at a dose of 1 mg/week. The SMAA demonstrated similar results to SUCRA.

WHAT IS NEW AND CONCLUSION

This is the first network meta-analysis that evaluated the efficacy and safety of dopaminergic agonists in the treatment of hyperprolactinemia. The results of this review revealed that these drugs have similar efficacy, but cabergoline has a better safety profile.

Role of gamma knife radiosurgery in the treatment of prolactinomas

PURPOSE

Stereotactic radiosurgery is one of the treatment options for prolactinomas, the most commonly used being Gamma Knife Radiosurgery (GKRS). GKRS is indicated mainly in the treatment of dopamine agonist (DA)-resistant prolactinomas. In our study, we report on our experience in treating prolactinoma patients by GKRS.

METHODS

Twenty-eight patients were followed-up after GKRS for 26-195 months (median 140 months). Prior to GKRS, patients were treated with DAs and 9 of them (32.1%) underwent previous neurosurgery. Cavernous sinus invasion was present in 16 (57.1%) patients. Indications for GKRS were (i) resistance to DA treatment (17 patients), (ii) drug intolerance (5 patients), or (iii) attempts to reduce the dosage and/or shorten the length of DA treatment (6 patients).

RESULTS

After GKRS, normoprolactinaemia was achieved in 82.1% of patients, out of which hormonal remission (normoprolactinaemia after discontinuation of DAs) was achieved in 13 (46.4%), and hormonal control (normoprolactinaemia while taking DAs) in 10 (35.7%) patients. GKRS arrested adenoma growth or decreased adenoma size in all cases. Two patients (8.3%) developed hypopituitarism after GKRS. Prolactinoma cystic transformation with expansive behaviour, manifested by bilateral hemianopsia, was observed in one patient.

CONCLUSIONS

GKRS represents an effective treatment option, particularly for DA-resistant prolactinomas. Normoprolactinaemia was achieved in the majority of patients, either after discontinuation of, or while continuing to take, DAs. Tumour growth was arrested in all cases. The risk of the development of hypopituitarism can be limited if the safe dose to the pituitary and infundibulum is maintained.

Hyperprolactinaemia in male infertility: Clinical case scenarios

Objective

To explore the evaluation, treatment and impact of hyperprolactinaemia on male infertility and testicular function, as hyperprolactinaemia is commonly detected during the evaluation of infertile men.

Methods

A literature search was performed using MEDLINE/PubMed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines to identify all studies exploring hyperprolactinaemia in male infertility.

Results

Elevated levels of serum prolactin have a detrimental effect on male reproduction through inhibition of the pulsatile release of gonadotrophins from the anterior pituitary gland, and a direct effect on spermatogenesis. Treatment of confirmed hyperprolactinaemia with dopamine agonists leads to significant improvements in both semen parameters and hormone levels.

Conclusion

Hyperprolactinaemia, both directly and indirectly, has a negative effect on sperm production, and its detection and management in men seeking fertility is mandatory.

Long-term results of cabergoline therapy for macroprolactinomas and analyses of factors associated with remission after withdrawal

OBJECTIVE

Withdrawal of cabergoline is generally challenging, especially in patients with large or invasive macroprolactinomas. Therefore, we aimed to assess long-term results of cabergoline therapy for macroprolactinomas and remission achievement results after withdrawal in patients with macroprolactinomas. We also investigated clinical characteristics and factors related to remission after withdrawal.

METHODS

This was an institutional review board-approved retrospective analysis. We studied 46 macroprolactinoma patients who had taken cabergoline during the period from 2003 through 2013. Administration of cabergoline was maintained for 5 years before withdrawal.

RESULTS

Median follow-up after the initiation of cabergoline therapy was 54·3 (range 5·3 to 137·2) months. Recurrences of hyperprolactinaemia were observed in 3 of 11 (27%) postwithdrawal patients at a median time of 3·0 (range; 2·9-11·2) months, indicating that a high percentage (73%) maintained remission for at least 12 months after cabergoline cessation. Factors significantly associated with remission were analysed in 21 patients receiving long-term cabergoline administration. On multivariate analysis, the absence of cavernous sinus invasion on pretreatment MRI (≥3/4 tumour encasement of the intracavernous internal carotid artery) (HR; 21·94, 95% CI; 2·06-1071·0, P = 0·006), initial PRL <132·7 ng/ml (HR; 8·28, 95% CI; 1·24-199·6, P = 0·03) and nadir PRL <1·9 ng/ml during cabergoline therapy (HR; 5·14, 95% CI; 1·10-39·02, P = 0·04) showed statistically significant correlations with remission after withdrawal.

CONCLUSIONS

Cabergoline therapy can achieve a high percentage (73% in this series) of remission maintenance for at least 12 months after cessation of a 5-year course of therapy, even in patients with macroprolactinomas. The absence of cavernous sinus invasion, serum PRL level lower than 132·7 ng/ml before cabergoline therapy or nadir serum PRL below 1·9 ng/ml were related to more frequent remission after withdrawal of cabergoline in patients receiving this medication for 5 years.

Medical treatment of male infertility

The majority of male infertility is idiopathic. However, there are multiple known causes of male infertility, and some of these causes can be treated medically with high success rates. In cases of idiopathic or genetic causes of male infertility, medical management is typically empirical; in most instances medical therapy represents off-label use that is not specifically approved by the FDA. Understanding the hypothalamic-pituitary-gonadal (HPG) axis and the effect of estrogen excess is critical for the assessment and treatment of male infertility. The use of certain medical treatment has been associated with an increase in sperm production or motility, and primarily focuses on optimizing testosterone (T) production from the Leydig cells, increasing follicle-stimulating hormone (FSH) levels to stimulate Sertoli cells and spermatogenesis, and normalizing the T to estrogen ratio.

Treatment of prolactinomas in low-income countries

Purpose. In low-income countries, prolactinomas are difficult to manage with dopamine agonists (DA). We compared the effectiveness of DA in microprolactinomas as a first line treatment and as adjuvant therapy for residual macroprolactinomas treated surgically. Methods. Our retrospective study analyzed 78 patients, 38 with microprolactinomas and 40 with macroprolactinomas. Microprolactinomas were treated with DA. Macroprolactinomas were treated with microsurgical or endoscopic adenomectomies and adjuvant DA. Surgical remission was defined as normoprolactinemia three months postoperatively, and long-term remission as normoprolactinemia at the last control. Results. Surgical remission was achieved in 9 patients (23%). Postsurgical tumor mass was reduced by 50% (34-68). Residual macroprolactinoma size was greater than microprolactinoma size prior to treatment (10 mm versus 4 mm, P < 0.001). Both groups received similar doses of DA. Long-term remission occurred in 68% of microprolactinomas and 43% of macroprolactinomas (P = 0.102). Prolactin (PRL) levels at the last control were similar in both groups (23.1 versus 32.9 mcg/L, P = 0.347). Conclusion. Comparable remission rates and PRL levels were reached in microprolactinomas and macroprolactinomas using similar doses of DA. Although complete tumor resection is the goal of surgery, our study suggests that even partial surgical removal has a role in treatment of prolactinomas since it may enhance the response to DA.

Prolactinomas resistant to standard doses of cabergoline: a multicenter study of 92 patients

BACKGROUND

Dopamine agonist resistance in prolactinoma is an infrequent phenomenon. Doses of cabergoline (CAB) of up to 2.0 mg/week are usually effective in controlling prolactin (PRL) secretion and reducing tumor size in prolactinomas. The clinical presentation, management, and outcome of patients that are not well controlled by such commonly used doses of CAB-resistant patients are poorly understood.

DESIGN AND METHODS

A multicenter retrospective study was designed to collect a large series of resistant prolactinoma patients, defined by uncontrolled hyperprolactinemia on CAB ≥2.0 mg weekly.

RESULTS

Ninety-two patients (50 F, 42 M) were analyzed. At diagnosis, most had macroprolactinomas (82.6%); males were significantly older than females (P=0.0003) and presented with a more aggressive disease. A genetic basis was identified in 12 patients. Thirty-six patients (39.1%) received only medical therapy, most underwent surgery (60.9%, including multiple interventions in 10.9%), and 14.1% received postoperative radiotherapy. Eight patients developed late CAB resistance (8.7%). The median maximal weekly dose of CAB (CAB(max/w)) was 3.5 mg (2.0-10.5). Despite a higher CAB(max/w) in patients treated with multimodal therapy (P=0.003 vs exclusive pharmacological treatment), a debulking effect of surgery was shown in 14 patients, with a higher rate of PRL control (P=0.006) and a significant reduction in CAB(max/w) (P=0.001) postoperatively. At last follow-up (median 88 months), PRL normalization and tumor disappearance were achieved in 28 and 19.9% of the patients respectively, with no significant sex-related difference observed in CAB(max/w) or disease control. Mortality was 4.8%, with four patients developing aggressive tumors (4.3%) and three a pituitary carcinoma (3.3%).

CONCLUSION

CAB-resistant prolactinomas remain a serious concern. Surgical debulking, newer therapeutic strategies, and early diagnosis of genetic forms could help to improve their outcome.

Cabergoline versus bromocriptine in the treatment of hyperprolactinemia: a systematic review of randomized controlled trials and meta-analysis

Cabergoline and bromocriptine are the most used drugs in the treatment of hyperprolactinemia, they are able to normalize the prolactin levels, restore gonadal function and promote tumor reduction in the majority of patients. We undertake a systematic review and meta-analysis of randomized controlled trials to compare cabergoline versus bromocriptine in the treatment of patients with idiopathic hyperprolactinemia and prolactinomas. The data sources were: Embase, Pubmed, Lilacs and Cochrane Central. The outcome measures were: normalization of prolactin secretion, restoration of gonadal function, reduction of tumoral volume, quality of life and adverse drug effects. Were identified 418 references and after screening by title and abstract, we obtained complete copies of 34 articles potentially eligible for inclusion in the review. From this total, 19 were selected to be included, but fifteen of them were excluded due to the following reasons: one randomized study compared cabergoline versus placebo and other randomized study compared different doses of cabergoline; five references were cases series; four were only controlled studies; three were retrospectives series and; one was a cohort study. Therefore, four publications were included in the review and in the final analysis. The meta-analysis of normalization of serum prolactin levels and menstruation with return of ovulatory cycle showed a significant difference in favor of cabergoline group (RR 0.67 [CI 95% 0.57, 0.80]) e (RR 0.74 [CI 95% 0.67, 0.83]), respectively. The number of adverse effects was significantly higher in the bromocriptine number than in cabergoline group (RR 1.43 [CI 95% 1.03, 1.98]). The meta-analysis showed new evidence favoring the use of cabergoline in comparison with bromocriptine for the treatment of prolactinomas and idiopathic hyperprolactinemia.

A randomized cross-over study comparing cabergoline and quinagolide in the treatment of hyperprolactinemic patients

Quinagolide (QUI) and cabergoline (CAB) are dopamine agonists recently introduced for the treatment of hyperprolactinemia. In the present study, these drugs have been compared in terms of effectiveness and tolerability. Twenty patients (18 females and 2 males) with hyperprolactinemia (8 with microprolactinomas, 6 with idiopathic hyperprolactinemia and 6 with empty sella turcica syndrome) were treated with oral QUI (75 microg once daily) and CAB (0,5 mg twice weekly), in a randomized cross-over trial with placebo between both drugs. Each drug was administered for 12 weeks, separated by other 12 weeks with placebo. PRL levels decreased with both drugs at 2 or 4 weeks of starting the treatment, without differences between both drugs at weeks 4, 8 and 12. At week 12, normal PRL levels (<20 ng/ml) were attained in 90% patients with CAB and only in 75% patients with QUI (p<0.05). After discontinuation of treatment, significant increase in serum PRL was higher after QUI withdrawal than after CAB. Clinical efficacy of both treatments was similar in terms of improvement amenorrhea, oligomenorrhea, galactorrhea, and impotence. All patients completed both cycles of treatment, and the most frequent side-effects were nausea, headache and dizziness, without significant differences between CAB (30%) and QUI (55%). Our study indicates that, at the doses employed here, CAB showed a high percentage of patients with normal PRL at the end of treatment and long-lasting efficacy in the levels of PRL. Clinical response and side-effects were similar in both drugs.

The effect of quinagolide and cabergoline, two selective dopamine receptor type 2 agonists, in the treatment of prolactinomas

OBJECTIVE

To compare effectiveness and tolerability of quinagolide (CV 205-502) and cabergoline (CAB) treatments in 39 patients with prolactinoma.

STUDY DESIGN

All 39 patients were treated first with quinagolide for 12 months and then with cabergoline for 12 months. A wash-out period was performed in all patients after 12 months of both treatments in order to evaluate recurrence of hyperprolactinaemia.

PATIENTS

Twenty-three patients with microprolactinoma (basal serum PRL levels 1620-18750 mU/l) and 16 patients with macroprolactinoma (basal serum PRL levels 4110-111000 mU/l), previously shown to be intolerant of bromocriptine. All patients had gonadal failure and 11 patients with macroprolactinoma had visual field defects. Five patients with macro- and one with microprolactinoma had previously undergone surgery.

STUDY PROTOCOL

The starting doses of quinagolide and CAB were 0.075 mg/day and 0.5 mg/week, respectively, subsequently increased up to 0.6 mg once daily and 1.5 mg twice weekly, respectively. Serum PRL levels were measured monthly for the first 3 months and then quarterly for 12 months. PRL levels were assayed weekly for the first month and then monthly during the wash-out period. Tumour shrinkage was evaluated by serial magnetic resonance imaging (MRI) studies of the hypothalamus-pituitary region at study entry and after 6 and 12 months of both treatments in micro- and macroprolactinomas.

RESULTS

After 12 months of quinagolide treatment, serum PRL levels normalized in all 23 patients with microprolactinoma (100%) and in 14 out of 16 with macroprolactinoma (87.5%). A tumour volume reduction of greater than 80% was documented by MRI studies in five of 23 (21.7%) patients with microprolactinoma and in four of 16 (25%) with macroprolactinoma. All patients had recurrence of hyperprolactinaemia after 15-60 days withdrawal of quinagolide treatment. However, before starting CAB treatment basal PRL levels were significantly lower than before quinagolide treatment both in microprolactinomas (4667.4 +/- 714.7 vs. 2636.1 +/- 262.3 mU/l, P = 0.006) and in macroprolactinomas (24853.1 +/- 7566.7 vs. 3576.6 +/- 413.0 mU/l, P = 0.013). After 12 months of CAB treatment, serum PRL levels normalized in 22 out of 23 patients with microprolactinoma (95.6%) and in 14 out of 16 with macroprolactinoma (87.5%). No difference in PRL nadir was found after quinagolide and CAB treatments both in micro 174.6 +/- 30.6 vs. 169.8 +/- 37.9 mU/l, P = 0.5) and in macroprolactinomas (277.5 +/- 68.4 vs. 341.8 +/- 95.2 mU/l, P = 0.6). A tumour volume reduction of greater than 80% was documented by MRI studies in seven other patients with microprolactinoma (30.4%) and in five other patients with macroprolactinoma (31.2%). After CAB treatment, further tumour shrinkage ranging 4-40% and 2-70% was observed in 12 micro- and seven macroprolactinomas, respectively. The percentage of tumour shrinkage after CAB was significantly higher than that observed after quinagolide in microprolactinomas (48.6 +/- 9.5 vs. 26.7 +/- 4. 5%, P = 0.046) but not in macroprolactinomas (47.0 +/- 10.6 vs. 26.8 +/- 8.4%, P = 0.2). The withdrawal from CAB treatment, induced an increase in serum PRL levels in all macroprolactinomas between 15 and 30 days, in 15 out of 23 microprolactinoma after 30 days, and in four patients after 2-4 months. In the remaining four patients serum PRL levels remained normal after 12 months of CAB withdrawal. Both compounds were tolerated satisfactorily by all patients. In the first week of quinagolide treatment, 12 patients reported nausea and postural hypotension, which spontaneously disappeared during the second-third week of treatment. None of the 39 patients reported side-effects during CAB treatment.

CONCLUSIONS

Both quinagolide and CAB treatments, induced the normalization of serum PRL levels in the great majority of patients with prolactinoma. Tumour shrinkage was recorded in 22-25% of patients after quinagolide and in 30-31% after CAB treatment

Clinical management of prolactinomas

Prolactinomas are benign, sporadic pituitary tumours that typically present with amenorrhoea and galactorrhoea in women, and hypogonadism and space-occupying effects in men. Hyperprolactinaemic hypogonadism in either sex is associated with reduced bone mineral density, which may be progressive and only partially reversible. For most microprolactinomas, dopamine agonists are the treatment of choice, achieving normoprolactinaemia and restoring gonadal function in 80-90% of cases. Trans-sphenoidal surgery is curative in 60%, but may be complicated by hypopituitarism and is usually reserved for patients with dopamine agonist intolerance or resistance. A subgroup of patients with small tumours, mild symptoms and normal gonadal function may be monitored without specific treatment--the risk of tumour expansion is small. Macroprolactinomas should be treated medically, dopamine agonists controlling prolactin secretion and achieving significant tumour shrinkage in 80% of cases, whereas surgery is curative in only a quarter. Cabergoline is the dopamine agonist of choice in most situations, being better tolerated and more effective than bromocriptine. Quinagolide is an effective alternative. Dopamine agonist withdrawal or dose reduction should be considered after 2-5 years therapy. Oestrogens may be used with caution in women with prolactinomas.

New medical treatment for acromegaly

The available somatostatin analogs for subcutaneous administration lower growth hormone (GH) levels in more than 90% of patients and Insulin-like growth factor-I (IGF-I) levels in up to 60%. They are also capable of reducing tumor size in up to 50%. Recently long-acting somatostatin analogs were introduced. The use of these application forms can result in normalization of IGF-1 in 60% of patients after 1 year and in 75% after 3 years. The development of selective analogs for the somatostatin receptor subtype-5 potentially will enhance the potency and the spectrum of the medical treatment of acromegaly with somatostatin analogs. The new generation of dopaminergic drugs also form a potentially effective and well tolerated therapy that should be considered in the management of those acromegalic patients, which have relative low serum IGF-I concentrations, along with high serum prolactine levels. Finally, growth hormone receptor (GHR) antagonists are under development for the use in humans. Preliminary results look promising, when biochemical parameters are concerned. Interim analysis of a phase 3 study with B2036-PEG in 38 patients does show that normalization of IGF-I concentrations is reached in at least 92% of the treated patients.

Successful Therapy for a Mixed Thyrotropin- and Prolactin-Secreting Pituitary Macroadenoma With Cabergoline

OBJECTIVE

To describe the first case of a mixed thyrotropin (TSH)- and prolactin-secreting pituitary macroadenoma that responded to therapy with cabergoline.

METHODS

We present a case report with clinical, laboratory, and radiologic details.

RESULTS

An 84-year-old woman with central hyperthyroidism due to a mixed TSH- and prolactin-secreting pituitary macroadenoma was successfully treated with orally administered cabergoline, 0.25 mg twice per week. Serial assays of thyroid and pituitary hormones were done, and magnetic resonance imaging of the pituitary was performed before and 16 weeks after initiation of cabergoline therapy. The patient had complete resolution of the increased pituitary hormone indices within 6 weeks after implementation of therapy, and these results were sustained for more than 16 weeks. A magnetic resonance imaging scan showed no change in tumor size at 16 weeks of therapy.

CONCLUSION

When medical treatment of TSH-secreting tumors is considered, choices of efficacious drugs are limited. To our knowledge, this report describes the first case of a long-acting dopamine agonist used successfully to control hypersecretion of a mixed TSH- and prolactin-secreting macroadenoma. Oral administration of cabergoline twice a week was effective, convenient, and well tolerated. Further evaluation of cabergoline, when indicated as medical therapy for TSH-secreting tumors, is warranted.

Drug-induced nightmares

OBJECTIVE

To compile and assess the English-language literature on drug-induced nightmares, excluding nightmares secondary to drug withdrawal or drug-associated night terrors.

DATA SOURCES

Published articles, letters, case reports, and abstracts in English were identified by MEDLINE (1966-May 1998) searches using the search term nightmares, chemically induced. Additional articles were obtained from bibliographies of retrieved articles.

DATA EXTRACTION

All case reports of drug-induced nightmares were evaluated using the Naranjo algorithm for causality. Clinical studies of drugs that reported nightmares as an adverse effect were assessed for frequency of occurrence.

DATA SYNTHESIS

Nightmares, defined as nocturnal episodes of intense anxiety and fear associated with a vivid, emotionally charged dream experience, are generally classified as a parasomnia. Possible pharmacologic mechanisms for drug-induced nightmares, such as REM suppression and dopamine receptor stimulation, are reviewed. However, the vast majority of therapeutic agents implicated in causing nightmares have no obvious pharmacologic mechanism.

CONCLUSIONS

Assessing causality with an event such as a nightmare is difficult because of the high incidence of nightmares in the healthy population. Using qualitative, quantitative, and possible pharmacologic mechanism criteria, it appears that sedative/hypnotics, beta-blockers, and amphetamines are the therapeutic modalities most frequently associated with nightmares. These drug classes have a plausible pharmacologic mechanism to explain this effect. Dopamine agonists also have evidence of causality, with dopamine receptor stimulation as a possible pharmacologic mechanism.

Impiego della cabergolina nella disfunzione erettile da prolattinoma: Cabergoline utilization in erectile dysfunction from prolactinoma

The authors report their experience in treating three men with cabergoline for micro- (one case) and macroprolactinoma (two cases). The clinical aspects plus hormonal and instrumental data prior to treatment are also reported. Clinical and hormonal evaluation was carried out 2, 3 and 6 months after therapy and CT after the sixth month. Results enabled the effectiveness of the drug to be checked.

Long-term and low-dose treatment with cabergoline induces macroprolactinoma shrinkage

Cabergoline (CAB), a long-lasting dopamine-agonist, specific for the D2 receptor, is effective in normalizing serum PRL levels in most patients with microprolactinoma or idiopathic hyperprolactinemia. Because few data are presently available on the effects of CAB treatment in macroprolactinomas, the aim of this open-label study was to investigate whether this drug was effective in producing tumor shrinkage, as well as in normalizing PRL levels. Twenty-three patients with macroprolactinoma entered this study 15 patients had had no treatment, whereas the remaining 8 patients had been previously treated with bromocriptine, which was with-drawn because of intolerance. Three of 23 patients had undergone unsuccessful surgery. Pretreatment serum PRL levels ranged from 100-3860 micrograms/L. CAB was administered at a dose of 0.5-3 mg once or twice a week for 12-24 months. Magnetic resonance imaging (MRI) scans were performed before and 3, 6, 12, and 24 months after the beginning of treatment, to evaluate tumor shrinkage, defined as a decrease of at least 80% of baseline tumor volume. After 3-6 months of treatment with a low dose (0.5-1 mg/week), serum PRL levels normalized in 18 patients. In the remaining 5 patients, whose serum PRL levels were not normalized, the dose was increased to 2-3 mg/week. This schedule caused the normalization of PRL levels in 1 patient, whereas in the remaining 4 patients, PRL levels were reduced to 30-82 micrograms/L. A tumor volume reduction greater than 80% at MRI occurred in 14 of 23 patients (61%) after CAB treatment (from 2609.4 +/- 534.7 to 530.1 +/- 141.3 mm3 at the 12-24th month follow-up, P < 0.001). A volume reduction of 41.8 +/- 3.4% was already evident after 3 months (1436 +/- 285.9 mm3; P < 0.001). The complete disappearance of the tumor mass at MRI occurred after 6 months of treatment with CAB in 1 patient, and in 5 patients after 1 yr of treatment. An improvement of visual field defects was obtained in 9 of the 10 patients presenting visual impairment before CAB treatment. The drug was tolerated well by all patients. Only 1 patient experienced mild nausea, which disappeared spontaneously after the 2nd day of treatment. Long-term, a low dose of the D2 receptor agonist CAB significantly reduced tumor volume and normalized serum PRL levels in a great majority of patients bearing macroprolactinoma. This treatment met with excellent patient compliance. This study suggests that CAB can be used as a first choice drug treatment in macroprolactinomas, as already shown for microprolactinomas and idiopathic hyperprolactinemia.

A comparison of cabergoline and bromocriptine in the treatment of hyperprolactinemic amenorrhea. Cabergoline Comparative Study Group

BACKGROUND

Cabergoline is a long-acting dopamine-agonist drug that suppresses prolactin secretion and restores gonadal function in women with hyperprolactinemic amenorrhea. We designed a study to compare its safety and efficacy with those of bromocriptine, which has been the standard therapy.

METHODS

A total of 459 women with hyperprolactinemic amenorrhea were treated with either cabergoline (0.5 to 1.0 mg twice weekly) or bromocriptine (2.5 to 5.0 mg twice daily), administered in a double-blind fashion for 8 weeks and subsequently in an open fashion for 16 weeks, during which adjustments in the dose were made according to the response. Of the 459 women, 279 had microprolactinomas, 3 had macroprolactinomas, 1 had a craniopharyngioma, 167 had idiopathic hyperprolactinemia, and the remainder had an empty sella. Clinical and biochemical status was assessed at 2-week intervals for 8 weeks and monthly thereafter for a total of 6 months, with an additional assessment at 14 weeks.

RESULTS

Stable normoprolactinemia was achieved in 186 of the 223 women treated with cabergoline (83 percent) and 138 of the 236 women treated with bromocriptine (59 percent, P < 0.001). Seventy-two percent of the women treated with cabergoline and 52 percent of those treated with bromocriptine had ovulatory cycles or became pregnant during treatment (P < 0.001). Amenorrhea persisted in 7 percent of the cabergoline-treated women and 16 percent of the bromocriptine-treated women. Adverse effects were recorded in 68 percent of the women taking cabergoline and 78 percent of those taking bromocriptine (P = 0.03); 3 percent discontinued taking cabergoline, and 12 percent stopped taking bromocriptine (P < 0.001) because of drug intolerance. Gastrointestinal symptoms were significantly less frequent, less severe, and shorter-lived in the women treated with cabergoline.

CONCLUSIONS

Cabergoline is more effective and better tolerated than bromocriptine in women with hyperprolactinemic amenorrhea.

Pharmacodynamics and relative bioavailability of cabergoline tablets vs solution in healthy volunteers

The effect of formulation on the urinary pharmacokinetics, pharmacodynamics, and relative bioavailability of cabergoline was investigated. Twelve healthy female volunteers, aged 23-35 years, were treated, according to an open, randomized, crossover design, with cabergoline (1-mg single oral dose) both as tablets and as a solution. The two administrations were separated by a 4-week wash-out period. Cabergoline and prolactin were measured in urine and plasma, respectively, by specific radioimmunoassays. Blood samples were collected before and up to 30 days after dosing. Urine was collected before and up to 8 days after dosing. Cabergoline elimination half-lives calculated from urinary data were 68 and 63 h after administration of the tablets and the solution, respectively. Urinary excretion of unchanged cabergoline accounted, on average, for 1.92% (range, 0.14-3.26) and 1.80% (range, 0.67-3.09) of the dose after administration of the tablets and the aqueous solution, respectively. Relative bioavailability of tablets vs solution was 99% (geometric mean with the 90% confidence intervals of 68-144%). Prolactin levels in 10 out of 12 subjects fell below the detection limit of the assay (1.5 micrograms/L) after both treatments. The mean maximum prolactin decrease (ca. 70%) was achieved by 2 or 3 h after dosing; the effect persisted up to 9 days, being completely exhausted 23-28 days after dosing. The analysis of variance performed on the pharmacodynamic effects of the two cabergoline formulations indicated that the percent decreases of plasma prolactin levels were not significantly different for tablets and solution. These results indicate that the pharmacodynamics and relative bioavailability of cabergoline are not influenced by formulation, as tablets or solution.

Treatment of prolactinoma patients with the new non-ergot dopamine agonist roxindol: first results

We studied the effects of the new non-ergot D2-dopamine agonist roxindol for the treatment of human prolactinomas. Roxindol is a non-ergot drug with additional 5-hydroxytryptamine type 1 A agonist and serotonin reuptake inhibitory activity. Ten patients with prolactin-secreting pituitary adenomas received roxindol three times daily at a dosage of 7.5-30 mg/day for at least 4 weeks according to a prospective protocol. All patients but one had received oral bromocriptine previously without normalization of prolactin levels. Serum prolactin profiles were analyzed once a week during the first month of therapy and at 4-week intervals thereafter. Mean baseline serum prolactin was suppressed from 23,000 +/- 13,600 mU/l (range 1500-141,000 mU/l; 20 mU/l = 1 microgram/l) by 37 +/- 11% after 1 week, by 49 +/- 9% after 4 weeks, and by 65 +/- 11% (n = 8) after 24 weeks of treatment. Serum prolactin was normalized in two patients. A tumor volume reduction of 20-25% was obtained in two subjects. Compared with previous treatment with oral bromocriptine the decrease in serum prolactin was comparable. In contrast, tolerance of roxindol was superior in five of seven patients with major side effects with bromocriptine, including three subjects who had discontinued bromocriptine because of adverse reactions. Four subjects spontaneously reported improvement of psychological and physical performance. One patient had a transient increase of serum transaminases. Thus, for the first time we could show a suppressive effect of roxindol on prolactin secretion in human prolactinomas. Due to its good tolerance roxindol may provide a useful alternative to bromocriptine.

A cross-over study with the two novel dopaminergic drugs cabergoline and quinagolide in hyperprolactinemic patients

Cabergoline and quinagolide, two new dopamine agonist drugs with long-lasting activity, are currently under investigation for the treatment of hyperprolactinemia. At present, studies comparing these drugs for tolerability and efficacy in the same patients are lacking. It was our aim to make such a comparison in an open randomized cross-over trial. Cabergoline (0.5 mg twice weekly) and quinagolide (75 micrograms once daily) were given orally. Each drug was administered for 12 weeks. Treatment with the second drug was started after the recurrence of hyperprolactinemia. Twelve women with hyperprolactinemia due to idiopathic disease (n = 6), microprolactinoma (n = 5) or postsurgical empty sella (n = 1) were evaluated. Six women were amenorrheic and 6 were oligomenorrheic. Ten had spontaneous or provoked galactorrhea. Baseline characteristics (age, clinical signs and PRL levels) of patients initially allocated to the two treatment groups were similar. Nine patients completed both treatment cycles and PRL levels were lower under cabergoline (10.7 +/- 3.7 micrograms/L) than under quinagolide (25.0 +/- 7.7 micrograms/L; p < 0.05). One patient discontinued cabergoline because of dryness of the eyes after having completed the quinagolide cycle and 2 patients initially treated with cabergoline discontinued quinagolide because of gastrointestinal symptoms. After completion of the first treatment cycle, the time of recurrence of hyperprolactinemia was significantly longer after cabergoline (14 +/- 7 weeks) than after quinagolide (5 +/- 1 weeks; p < 0.05). At week 12, normal PRL levels (< 20 micrograms/L) were observed in 10 and 6 women during cabergoline and quinagolide, respectively. Only one case was resistant to both drugs. The clinical effects of the two treatments were similar.(ABSTRACT TRUNCATED AT 250 WORDS)

The efficacy and tolerability of long-term cabergoline therapy in hyperprolactinaemic disorders: an open, uncontrolled, multicentre study. European Multicentre Cabergoline Study Group

OBJECTIVE

We assessed the efficacy and safety of the new, long-acting dopamine agonist drug cabergoline during long-term therapy of hyperprolactinaemia.

DESIGN

Open, prospective, multicentre study.

PATIENTS

One hundred and sixty-two females with either a microprolactinoma (n = 100), idiopathic hyperprolactinaemia (n = 54), empty sella syndrome (n = 7) or residual hyperprolactinaemia after surgery for a macroprolactinoma (n = 1). All had previously been treated with cabergoline or placebo for 4 weeks as part of a dose-finding study.

MEASUREMENTS

Menstrual pattern, adverse symptoms, blood pressure and pulse, serum PRL, blood count, liver and renal function were assessed after one month and subsequently at two-monthly intervals.

RESULTS

Treatment was started at doses of 0.25 mg (n = 3), 0.5 mg (n = 8), 1 mg (n = 150) or 2 mg (n = 1) per week, given either as a single weekly dose (n = 8) or divided into twice-weekly doses (n = 154), and was continued for at least 49 weeks in 123 patients. Final treatment doses ranged from 0.25 mg fortnightly to 2 mg twice weekly: most patients finished the study taking 0.5 mg once (n = 31) or twice (n = 77) weekly. Stable normalization of PRL levels was achieved in 138 subjects (85%), in 129 of whom the effective dose was < 1 mg per week. In the subset of 114 patients completing 49 weeks of therapy and having dose adjustments according to the protocol, the biochemical success rate was 92%. Fifty-nine of the 65 previously amenorrhoeic women (91%) and 44 of the 49 (90%) who were previously oligomenorrhoeic resumed regular menses and/or became pregnant during the study. Adverse events were reported in 64 patients (39.5%). In 84% of cases with adverse events, the symptoms were of mild or moderate severity and most occurred during the first few weeks of therapy; five patients (3%) discontinued treatment because of poor tolerance. The most frequent symptoms were dizziness (13% of patients), headache (13%), nausea (10%) and weakness and/or fatigue (10%). Of 27 patients who had previously been poorly tolerant of other dopamine agonists, 17 (63%) did not experience any side-effects and only one was intolerant of cabergoline. No adverse haematological or biochemical effects were detected except for a slight downward trend in haemoglobin which may have been related to the resumption of regular menses in previously amenorrhoeic or oligomenorrhoeic women. A mild hypotensive effect was observed, mean systolic and diastolic blood pressures falling by 5 and 4 mmHg respectively during treatment.

CONCLUSIONS

The results provide evidence for the long-term effectiveness and safety of cabergoline in the treatment of hyperprolactinaemia. Its ability to normalize PRL and restore gonadal function compares favourably with reported data on reference compounds while its tolerability profile and simple administration schedule offer potential advantages in terms of patient acceptability.