Effect of Inhaled Alpha-Blocker on Airflow Obstruction in Asthma1

A controlled study of the effect on airflow obstruction of 30 mg of the alpha-blocker thymoxamine given by inhalation is reported in 10 patients with chronic stable asthma. No significant change in peak expiratory flow rate was seen with either thymoxamine or placebo in any patient. Alpha-adrenergic receptors are therefore unlikely to contribute significantly to resting bronchomotor tone in chronic stable asthma.

Are alpha-blockers involved in lower urinary tract dysfunction in multiple system atrophy? A comparison of prazosin and moxisylyte

Lower urinary tract dysfunction is a major cause of morbidity in patients with multiple system atrophy (MSA). alpha1-Adrenergic receptors are present in the proximal urethra where impaired relaxation may be responsible for voiding difficulty and a large amount of residual urine. An open study was designed to evaluate whether the blockade of these receptors by prazosin (a nonselective alpha1 blocker) and moxisylyte (an alpha1A-selective blocker) would improve bladder emptying in patients with MSA. Post-micturition residual volumes and clinical symptoms of 49 patients with MSA were evaluated at trial entry and after 4 weeks (prazosin; n=21 and moxisylyte; n=28). The respective means for the prazosin and moxisylyte groups were 38.1% and 35.2% reductions in residual urine volume (P<0.05), and there was lessening of urinary symptoms. Side effects due to orthostatic hypotension were seen in 23.8% of the prazosin group but in only 10.7% of the moxisylyte group. These effects were common in patients with postural hypotension of more than -30 mmHg at trial entry (P<0.05). Modulation of alpha1-receptors may function in the management of lower urinary tract dysfunction in MSA.

Moxisylyte: a review of its pharmacodynamic and pharmacokinetic properties, and its therapeutic use in impotence

Moxisylyte is a competitive noradrenaline antagonist, acting preferentially on post-synaptic alpha-1 adrenoceptors. It was introduced more than thirty years ago for the treatment of cerebro-vascular disorders and shown more recently effective in the urological field due to its ability to modulate the urethral pressure. Renewal of interest in this drug has been observed in recent years since the demonstration of the possibilities of vasoactive drugs in evaluation and treatment of erectile dysfunctions. Moxisylyte is a prodrug, rapidly transformed into an active metabolite in plasma (Deacetylmoxisylyte or DAM). Elimination of the active metabolite occurs by N-demethylation, sulpho- and glucuroconjugation. The N-demethylated metabolite is sulphoconjugated only. Urine is the main route of excretion. The metabolites of moxisylyte can be determined in biological fluids by various methods using high-performance liquid chromatography. Their pharmacokinetics is dependent on the route of administration. By the oral route, the concentrations of the active metabolite are low, and the glucuroconide of DAM predominates over the sulphates. After intravenous and intracavernous injection, the active metabolite is proportionally higher, the two sulphates are equivalent and in larger amounts than the glucuronide. In the treatment of impotence, intracavernous injection of moxisylyte at 10, 20 or 30 mg can induce an erection adequate for intercourse in most of the patients. Compared to inducing agents such as papaverine and prostaglandin E1, moxisylyte must be considered as a facilitator of male erection, its interest lying in the low rate of adverse effects, either general or local.

Double-blind multicenter study comparing alprostadil alpha-cyclodextrin with moxisylyte chlorhydrate in patients with chronic erectile dysfunction

PURPOSE

We compared the efficacy and safety of alprostadil alpha-cyclodextrin and moxisylyte chlorhydrate to induce erections adequate for sexual intercourse in a prospective, randomized, parallel double-blind study in patients with erectile dysfunction.

MATERIALS AND METHODS

A total of 156 men with erectile dysfunction due to organic, nonorganic and mixed origin was randomized into 2 parallel treatment groups receiving titrations of an individual optimum dose of alprostadil alpha-cyclodextrin or moxisylyte chlorhydrate. Erectile response was measured by the buckling test. A positive test was associated with axial erection rigidity that did not buckle/deform to 1.0 kg. load. The buckling test was repeated every 10 minutes for up to 60 minutes.

RESULTS

A total of 56 patients (75%) in the alprostadil alpha-cyclodextrin group and 32 patients (40%) in the moxisylyte chlorhydrate group responded with at least 1 positive buckling test during the office period. Investigators assessed erections after alprostadil alpha-cyclodextrin to be adequate for sexual intercourse in 61 patients (81%) compared to 37 patients (46%) after moxisylyte chlorhydrate. All efficacy parameters in office reached statistical significance of p < 0.001 in favor of alprostadil alpha-cyclodextrin. During self-injection therapy at home 58 patients (85%) reported at least 1 rigid erection after alprostadil alpha-cyclodextrin compared to 37 patients (61%) after moxisylyte chlorhydrate. Patient and partner opinion of treatment achieved statistically significantly better scores in the alprostadil alpha-cyclodextrin group compared to the moxisylyte chlorhydrate group.

CONCLUSIONS

Alprostadil alpha-cyclodextrin is significantly more effective than moxisylyte chlorhydrate in producing full penile rigidity in office and at home. Injection related side effects occur with the same frequency but moxisylyte results in more systemic side effects and alprostadil results in more painful and prolonged erections. Patients and partners are significantly more satisfied with alprostadil alpha-cyclodextrin.

Intracavernous pharmacotherapy: comparison of Moxisylyte and prostaglandin E1

We report in this retrospective study the results obtained with the first two drugs proposed to reduce the relatively high rates of priapism and fibrosis bound to the papaverine intracavernous injections, i.e. the alpha-blocking agent Moxisylyte (Mox), and prostaglandin E1 (PGE1). Each drug was used for auto-injections in 130 patients with a comparable mean follow up (14.8 months with Mox compared to 14.6 with PGE1). PGE1 proved to be significantly more efficacious (good results in 71% of the patients vs 50% with Mox), especially in the arteriogenic patients (respectively 96% vs 46%). Conversely PGE1 induced prolonged erections in significantly more patients (11 vs 1 with Mox), including 2 priapisms, and also induced pain in more patients (12 vs 1 with Mox). The rate of fibrotic nodules and plaques was low (2 and 3 patients). Despite the better tolerance of Mox, its continuation rate was significantly lower than that of PGE1, PGE1 can be the first choice agent in most cases. Mox is mainly indicated in the patients with supersensitivity to the injections and in those with significant pain following PGE1.

[Prolonged use of moxisylyte chlorhydrate (Icavex) by intracavernous self-injections in the treatment of impotence. Evaluation of long-term tolerance]

Moxisylyte chlorhydrate is a selective alpha-blocker of the post-synaptic alpha 1-adrenoreceptors. It has been used since 1992 for self-injections to induce erection. Tolerance has been studied in open trials in 143 men using 20 mg per intracavernous injection. Among these subjects, 104 were followed for 11 months. Self-administration was performed 7,509 times, i.e. 49.1 injections per subject over a mean period of 307 days. No severe side effects were observed. A total of 1,041 undesirable effects were reported by 90 subjects (75.1%), including mechanical disorders (28.2%) such as pain and burning sensation at injection, hematomas and ecchymoses. Nodules developed in 0.08% of these cases but always regressed. In 71.8% of the cases, the undesirable events was imputable to moxisylyte: dry mouth (2.73%), somnolence (1.9%), sinus congestion (0.71%). No case of priapism was reported. Long-term evaluation showed a reduction in the main undesirable effects with time. This fall off in the mechanical events could be explained by the subjects become for familiar with the technique. Pharmacological effects remain to be analysed. Added to the good tolerance, this result suggests that self-injection can be proposed as a first intention treatment for impotency.

[Treatment of erectile insufficiency]

Impotency, or impaired erectile function, affects approximately 10% of the adult males in France. The psychological consequences can have a major impact not only on the subject's sexual life but also his familial and professional relationships. The task facing the urologists is to carefully evaluate the patient's request for care and adapt treatment not only to the physiological situation but also the patient's psychological and social context. Several approaches have been developed. Search for an aetiology, excepting exceptional cases with a recognized organic origin, is often unsatisfactory due to the multifactor processes involved and the self-sustaining inter-relationship between the psychological impact and the physiological disorder. Sex therapy is aimed at reducing anxiety and helping the couple better understand their sexual relationship. Such behavioural counselling is particularly indicated in absence of organic disorders or as complementary therapy combined with medical or surgical treatment. The pharmacological approach relies on alphablockers or certain psychotropic drugs which have a moderate but real effect when taken orally. Local non-invasive applications of protaglandin E1 can also improve erectile function. The mechanism of intrapenial injections is to release the erectile smooth muscles. The most widely used drugs in France are papaverine, phentolamine and moxisylite as well as prostaglandin E1. Self-injections may be required in certain cases but are abandoned by about half of the patients after one or two months. Vacuum with a mechanical pump can produce a non-physiological erection but is rarely used in France. Surgical repair of arterial or venous disorders can also provide excellent, particularly long-term, results in carefully selected patients. Despite undeniable progress, the treatment of impotency remains a difficult therapeutic challenge, basically due to the large number of casual factors and their complex interactions.

[Changes in urethral pressure after intravenous injection of moxisylyte hydrochloride in urethral instability in women. Preliminary results]

OBJECTIVE

To study the action of an alpha blocker, Moxisylyte hydrochloride, during an intravenous test on the course of urethral pressure in women with urethral instability associated with urethral hypertonia.

METHODS

The population consisted of 20 women with a mean age of 38 years, presenting with a clinical disorder of micturition (urinary incontinence: 15 cases, urgency: 17 cases, frequency, 17 cases) present for an average of 4 years and associated with resting urethral pressure variations ranging from 22 to 88 cm H2O (mean: 44.8 cm H2O) and static urethral pressures ranging 72 to 150 cm H2O (mean: 102.5 cm H2O). An urodynamic assessment was performed before and after intravenous injection of Moxisylyte hydrochloride at the dose of 0.5 mg/kg.

RESULTS

Moxisylyte hydrochloride induced a significant reduction of urethral pressure variations, ranging from 8 to 42 cm H2O (mean: 21.9 cm H2O) and static urethral pressures, ranging from 47 to 102 cm H2O (mean: 68.8 cm H2O). Treatment was well tolerated in every case.

CONCLUSION

These preliminary results need to be completed by a randomized placebo-controlled study to confirm a statistically significant effect of Moxisylyte hydrochloride on urethral pressure stability in women presenting with urethral instability.

The antimigraine effect of ergotamine: a role for alpha-adrenergic blockade?

The hypothesis that alpha-adrenergic receptor blockade accounts for the ability of ergotamine to stop migraine attacks was tested, in migraine patients, in an experimental migraine model based on nitroderivative- induced attacks. In a preliminary single blind, placebo controlled study, thymoxamine, a prevalently post-synaptic alpha adrenergic receptor antagonist, was able to abort migraine attack in 9 out of 10 patients, as opposed to 2 out of 10 by placebo (p < 0.005 Fisher's exact test). In a subsequent randomized, crossover, placebo controlled double blind study, the ability of a selective alpha-1 adrenergic receptor agonist, methoxamine, to block ergotamine antimigraine effect was studied. In 26 patients migraine was induced in two separate tests and then ergotamine was administered once after methoxamine pretreatment and once after placebo; methoxamine was significantly more effective than placebo in blocking antimigraine effect of ergotamine (p = 0.0055 Fisher's exact test). These results support the hypothesis that ergotamine alpha-1 adrenolytic properties may account for its antimigraine effect suggesting that this action takes place outside the blood-brain barrier, since methoxamine can cross it very poorly. Ergotamine target structure could be the trigeminal innervation of the extracranial and/or dural vessels.

Thymoxamine in the treatment of traumatic mydriasis

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Efficiency and side effects of intracavernous injections of moxisylyte in impotent patients: a dose-finding study versus placebo

We assessed the efficiency and tolerance of the alpha-blocking agent moxisylyte in 2 double-blind studies versus placebo performed in 12 neurogenic patients with spinal cord lesions and in 61 patients presenting with either psychogenic impotence (30) or erectile dysfunction that was predominantly neither psychogenic, hormonal nor neurogenic (31). In each etiological group patients were randomized (according to latin square method) to receive 3 single doses (10, 20 and 30 mg.) of moxisylyte and a placebo. The erectile response was determined 5, 10, 15, 20 and 30 minutes after each injection. Whatever etiology of impotence and dosage tested, the erectile response induced by moxisylyte was significantly higher than the placebo-induced response. No difference occurred among the 3 doses. In 93% of the patients moxisylyte induced an erectile response, including tumescence in 6, partial rigidity in 16 and complete rigidity in 46. Thus, in 62 of 73 patients (85%) the drug allowed initiation of erection adequate for intercourse. Placebo induced such erection in only 25% of the cases and in 55% there was no response. Tolerance was good and no priapism occurred. Only 4 patients (5%) reported mild pain during injection but erections were never painful, 1 presented with moderate and transient hypotension at the 20 mg. dose and a painless prolonged erection was observed in 1 case after the lowest dose. Drugs such as moxisylyte should be given before less well tolerated drugs.

[Treatment of impotence with intracavernous auto-injections: moxisylyte diminishes the risks compared to papaverine]

The alpha-blocking agent Moxisylyte was tested in auto-intracavernous injections (auto-ICI) in 72 impotent patients. The side-effects were compared to those observed in a group of 34 impotent patients treated with auto-ICI of Papaverine during the same period of time. The Moxisylyte auto-ICI improved 83% of the patients including 68% reporting a complete and durable success. Moxisylyte proved to be safer due to a reduced rate of prolonged erections (1.3% of the patients versus 8.8% with Papaverine) and corporeal fibrosis (1.3% versus 32% with Papaverine). Though less potent than Papaverine, and often seeming insufficient when tested in the office, this type of alpha-blocking agent could be tried in a first time in most candidates to auto-ICI before resorting to Papaverine or Prostaglandin E1 if it fails.

Is the volume injected a parameter likely to influence the erectile response observed after intracavernous administration of an alpha-blocking agent?

In 12 impotent patients with spinal cord injury, we assessed the erectile response induced by intracavernous administration of 20 mg moxisylyte dissolved in 4 different volumes of solvent. We tested successively in each patient 0.4, 0.8, 1.2 ml and the volume usually injected of 2 ml, with a 7-day interval between 2 injections. The reduction in the volume from 2 to 0.4 ml did not thwart the quality of erection obtained by the intracorporeal administration of 20 mg moxisylyte. Indeed, for each erectile parameter (rigidity, abdominopenile angle, length and circumference of the penis), no statistically significant difference arose between the 4 tests. All patients achieved full rigidity. Neither priapism nor prolonged erection occurred. These results suggest that discreet and easily handled small-sized injection pens, containing little solution, could be conceived for autoinjection therapy.

Adjuvant drug therapy: a review of 30 cases of sacral anterior root stimulator

Implantation of a sacral anterior root stimulator in spinal cord injured patients must achieve two main goals to maintain a vesicosphincteral balance: complete bladder voiding and correct continence. During the postoperative period, difficulties may arise or persist with either an incontinence due to an insufficient deafferentation with bladder hyperreflexia or an incomplete voiding because of an insufficient contraction of detrusor and/or too high urethral resistances (vesicosphincteral dyssynergia). A third of our patients required specific therapies after implantation to promote interstimulation continence and complete bladder voiding. Regarding continence, adjuvant therapies are effective for bladder hyperreflexia in connection with a too-partial deafferentation. On the other hand, these therapies have little effect on low bladder compliance. In regard to bladder voiding, nonsurgical treatments are equally effective. These treatments (parasphincteral infiltrations, alpha-blockers) must not be permanent, but allow a reharmonizing between expulsive strengths and urethral resistances. Eighty percent of our patients who required adjuvant therapies have been improved significantly. This confirms the efficiency of adjuvant therapy and speaks for patience.

[The combination of oral trazodone-moxisylyte: diagnostic and therapeutic value in impotence. Report of 110 cases]

An oral drug treatment was prescribed systematically for one month in 110 unselected patients suffering from impotence: Tradozone (75 mg/day)+Moxisylite (180 mg/day) daily, or at higher doses if possible, and Trazodone (25 mg/day)+Moxisylite (60 mg/day) one hour before any sexual intercourse. Adverse effects were uncommon (6.3%). Satisfactory sexual activity was restored in 28% of cases and an improvement in spontaneous erections was obtained in 42% of cases. No improvement was observed in 30% of cases. This oral drug test therefore presents 3 advantages: a) it facilitates the diagnosis and treatment of impotence by eliminating moderate forms of psychogenic impotence, b) it reduces both the morbidity and cost of investigation of impotence by reducing the number of tests performed, c) it emphasizes the role of oral treatment in impotence. In conclusion, this oral drug test should be used because of its simplicity, safety and real efficacy. The current objectives of this test are to improve the efficacy of oral treatment as a result of pharmacological progress.

The efficacy of thymoxamine in primary Raynaud's phenomenon

A randomised double-blind, three-way cross-over trial comparing oral thymoxamine 40 mg, oral thymoxamine 80 mg with a matched placebo was performed in 24 patients with primary Raynaud's phenomenon. The response to treatment was objectively assessed by monitoring digital skin temperature response for 7 min after exposure to a mild cold stimulus (20 C for 1 min). Thymoxamine treatment "normalised" rewarming responses in a statistically significant number of patients (P less than 0.01). Absolute digital temperatures and maximum rewarming rates were increased and the length of the latent period reduced (P less than 0.001). These effects were more pronounced with thymoxamine 80 mg than with thymoxamine 40 mg.

Safety of intracavernous injections using an alpha-blocking agent

We tested the possibility of using intracavernous injections of the alpha-blocking agent moxisylyte (6-acetoxy-thymoxy-ethyl-dimethylamine) as treatment of erectile impotence. Laboratory studies proved moxisylyte to be more active than saline (double-blind with crossover) but less active than papaverine (crossover), since it induced prolonged erection in most patients but rigid erection in only a few. However, penile vibration proved to enhance the moxisylyte effects, the combination resulting in rigid erection in 5 of 8 patients tested. Repeated office injections of moxisylyte in 70 patients resulted in clear improvement of impotence during the subsequent weeks in 50 per cent of the psychogenic, and 18 per cent of the organic and mixed impotent patients. Of 91 impotent patients 42 achieved satisfactory intercourse within 2 hours after an office injection, although previously the same dose induced a rigid erection in the office in only 24. Of 37 patients instructed in moxisylyte self-injections 92 per cent achieved successful results without any significant side effect. The main advantage of moxisylyte proved to be its safety, allowing for less compelling precautions than with papaverine: only 2 of the 170 patients injected with moxisylyte at our clinic had prolonged erections, that is 1.1 per cent compared to 14 per cent in a personal series who received papaverine. In regard to the therapeutic applications of intracavernous injection facilitating drugs, such as moxisylyte, should be tried first, with use of the more potent but also more dangerous drugs, such as papaverine, only when impotence fails to improve.

[Conservative treatment of glaucoma]

The author presents conservative treatment of glaucoma. Pharmacologic action of antiglaucoma drugs from group of mioties, and adrenergic blockers and other hypothension agents is discussed. Furthermore side effects of these drugs and their synergic action is presented. Personal experience connected with it is also discussed.

[The effect of moxisylyte hydrochloride in the symptomatic treatment of benign prostatic hyperplasia]

The clinical effectiveness of moxisylyte hydrochloride (Moxyl, Fuji Rebio), a selective alpha 1-adrenoceptor blocking agent, was investigated in patients with symptomatic benign prostatic hyperplasia. Moxisylyte hydrochloride was administered at the dose of 90 mg per day orally for four weeks. Residual urine sensation was improved in 9 out of 17 cases (53%), retarded urination in 14 out of 19 (74%), prolonged urination in 12 out of 19 (63%), weak stream in 14 out of 21 (67%) and strained voiding in 11 out of 19 cases (58%). Residual urine volume and residual urine ratio were decreased in 14 out of 21 cases (67%), maximum urine flow rate was increased in 14 out of 21 (67%) and mean flow rate was increased in 15 out of 21 cases (71%). There was, however, no statistical significance between pre- and post drug administration in objective parameters. Our open trial showed that the subjective efficacy of moxisylyte hydrochloride was 82% (18/22 cases), the objective one was 59% (13/22 cases) and overall efficacy was 77%. Side effects were observed in four of all subjects (18.2%), and drug administration had to be ceased in only one of these patients due to mild dizziness. Other side effects were mild nausea, headache and chest discomfort. Decrease in blood pressure was not seen in all but one case.

Effect of moxisylyte hydrochloride on isolated human penile corpus cavernosum tissue

The effect of moxisylyte hydrochloride on isolated human penile corpus cavernosum tissue was investigated and compared with other a-adrenergic antagonists. Moxisylyte produced a concentration-dependent relaxation of a norepinephrine-induced (1 x 10(-5) M) contraction of the corpus cavernosum tissue. Pretreatment with 1 x 10(-6) M doses of moxisylyte reduced competitively the norepinephrine-induced contraction. The competitive effect of prazosin was strongest among four tested agents, followed by phentolamine, moxisylyte, and then yohimbine. The activity ratio for each antagonist is 2.4 for moxisylyte, as compared with 28.2 for prazosin, 6.7 for phentolamine, and 1.6 for yohimbine respectively. Moxisylyte hydrochloride is an agent with potential clinical and research uses capable of producing erection when injected intra-cavernously.

Thymoxamine: a miotic for intraocular use

Thymoxamine hydrochloride can be used intraocularly to reverse phenylephrine or epinephrine mydriasis during intraocular surgery (0.2-0.5 ml of 0.01% or 0.02% solutions proved to be effective). No endothelial damage was found up to a dose of 1 ml of 0.02% thymoxamine in animal experiments using a physiologically buffered solution. Since stability is low in the buffered state, the final concentration has to be prepared at the time of surgery using a 0.5% solution and a phosphate buffer. Intracameral thymoxamine is a potent miotic during operations and can be helpful in extracapsular cataract surgery, keratoplasty, and repair of perforating injuries.

Ergotamine-induced peripheral ischaemia reversed by oral thymoxamine hydrochloride

Although there is no generally accepted therapy for ergotamine-induced vasoconstriction, infusion of directly acting vasodilators is regarded presently as the treatment of choice. We present a case of peripheral arterial ischaemia secondary to excessive use of ergotamine suppositories, which was reversed with oral thymoxamine hydrochloride (an alpha 1-adrenoceptor antagonist) and ergotamine withdrawal. We suggest that in patients with ergotamine-induced peripheral arterial vasoconstriction with no evidence of gangrene, oral thymoxamine may be considered as a useful adjunct or possible alternative to infused vasodilator treatment.

Differential effects of alpha-adrenoceptor blockade on essential, physiological and isoprenaline-induced tremor: evidence for a central origin of essential tremor

Intravenous thymoxamine reduced the power of essential tremor but increased that of physiological and isoprenaline-induced tremor. These findings indicate that essential and physiological tremor have dissimilar pathophysiological mechanisms. They also suggest that central adrenergic mechanisms are involved in the pathophysiology of essential tremor and that isoprenaline-induced tremor is not a good model of essential tremor. Furthermore, alpha-adrenoceptor blockers may be a useful therapy for essential tremor.

[The effect of antiglaucoma drugs on the depth of the anterior chamber (I)]

The Authors have taken into account the most common effect of antiglaucomatous drugs on the depth of the anterior chamber. The modifications of the anterior chamber have been evaluated utilizing a Jaeger Pachymeter. The values were obtained before the drug instillation and an hour afterwards. The results are presented as the mean and standard deviation. Among the examined drugs, only miotics have brought about a notable decrease, whereas the others have shown no significant effects.

Reduction of systemic vascular resistance by competitive alpha adrenergic blockage with thymoxamine after cardiopulmonary bypass for cardiac operations

Fifteen patients with evidence of excessive systemic vasoconstriction following cardiac operations were studied. Serial hemodynamic measurements were made before and during infusion of thymoxamine, a competitive alpha adrenergic blocking drug. Thymoxamine resulted in a full in systemic resistance together with a rise in cardiac index without reflex tachycardia. When thymoxamine was infused at a rate of 1 mg . kg-1, the desired effect was achieved without sudden profound falls in arterial pressure and there were no significant side effects. During the first few hours after bypass, skin temperature measurements do not give an adequate indication of the circulatory state. Measurement of mixed venous oxygen saturation is a most useful, simple method of monitoring the acute effects of treatment during this period.

Thymoxamine hydrochloride: an alpha-adrenergic blocker

Thymoxamine is an alpha-adrenergic blocking agent which works by competitive antagonism of norepinephrine. It is the only alpha-adrenergic blocker available which has tolerable side effects when used as an ophthalmic solution. When used as a 0.5% solution it consistently produces miosis without affecting the intraocular pressure or the ciliary muscle-controlled facility of outflow. The only regularly reported side-effects at this concentration are transient burning and conjunctival hyperemia. Potential applications of thymoxamine include reversal of phenylephrine mydriasis, treatment of angle-closure glaucoma, treatment of persistent mydriasis after penetrating keratoplasty for keratoconus, reversal of lid retraction in thyroid ophthalmopathy, testing to differentiate angle-closure glaucoma from open-angle glaucoma with narrow angles, aiding in repositioning and maintaining the position of intraocular lenses, treatment of pigmentary glaucoma. Thymoxamine may also contribute to a better understanding of the adrenergic nervous system on aqueous dynamics.

Case report of ?hormonal vertigo

A case-history of episodic vertigo, extending over 25 years, is reported. This case was twice investigated from the neurological standpoint without a definite conclusion being reached. Eventually a hormonal-electrolyte disturbance was postulated and, to some extent, established by prolonged observation and treatment.

Effect of thymoxamine in the relief of pain and rate of healing in ischaemic leg ulceration

A small uncontrolled pilot study was carried out in 6 patients with ischaemic leg ulceration in which pain was severe to assess the effectiveness of thymoxamine in the relief of pain and on the rate of healing. Patients were treated for 3 days with intravenous injections of 0.1 mg thymoxamine/kg body weight and then with oral 40 mg thymoxamine 4-times daily for a further month. The results showed that there appeared to be a definite improvement in pain during intravenous therapy and this was maintained to a large extent, although not so definite, on oral therapy. No enhanced rate of healing, however, was evident.

The use of thymoxamine in eyelid retraction

We observed substantial narrowing in 75% of fissures in patients with various types of lid retraction after topical application of aqueous 0.5% thymoxamine (moxisylyte). Even contralateral normal-appearing fissures in thyroid patients responded in this manner. The nonresponders in the lid retraction group included a patient with an orbital pseudotumor and patients with long-standing and stable euthyroid eye disease. No normal subjects' fissures responded greatly to thymoxamine. A substantial reduction in palpebral fissures was seen in all patients with thick extraocular muscles and in 14 of 18 (78%) of all fissures of thyroid patients; the average response was 2.3 mm. This effect may last for five hours after thymoxamine administration. Thymoxamine may be of use as a diagnostic test for thyroid eye disease, and if it can be modified to cause less ocular irritation, it may be beneficial in the medical treatment of eyelid retraction.

The effects of thymoxamine on anterior chamber depth in human eyes

The effects of 0.5% Thymoxamine on intraocular pressure and anterior chamber depth were studied in 20 non-glaucomatous eyes. Miosis occurred in all of the eyes but was not accompanied by a shallowing of the anterior chamber or reduction in the intraocular pressure. The significance of the findings is discussed.

Thymoxamine test. Differentiating angle-closure glaucoma form open-angle glaucoma with narrow angles

To help differentiate mild angle-closure glaucoma from open-angle glaucoma in patients with elevated intraocular pressure (IOP) and angles so narrow that the structures cannot be seen adequately, we used a thymoxamine hydrochloride eyedrop that induces miosis and tends to widen the angle. Thymoxamine does not contract the ciliary muscle and does not alter the IOP or facility of outflow in open-angle glaucoma, but it can relieve angle-closure glaucoma. A test with thymoxamine was performed in 26 patients because of this differential diagnostic dilemma. When gonioscopic, tonometric, and tonographic findings appeared to indicate a diagnosis of angle-closure glaucoma, a peripheral iridectomy was done. Subsequent (one to 27 months) observations have substantiated that testing with thymoxamine is a helpful aid in this differential diagnosis, and merits more widespread evaluation.

Retrospective assessment of thymoxamine (Opilon) in treatment of Ménières disease

A retrospective study of 305 patients treated with thymoxamine (Opilon) for Ménières disease is described. Thymoxamine controlled symptoms in 78.7% of patients and the time to maximum improvement ranged from six weeks to three months. Seven patients suffered side-effects.

Depression of spasticity by alpha-adrenergic blockade

In spastic patients the alpha-adrenergic blocking drug thymoxamine (Opilon Forte) was found capable of depressing most propioceptive reflex parameters within 1 min after intravenous administration. The action seems to be of CNS origin, probably exerted as a depression of spindle stretch sensitivity through descending alpha-adrenergic bulbospinal pathways, but an additional action on the mechanism of presynaptic inhibition is likely. With oral administration, the drug is also capable of depressing distressing clonus, and it is concluded that it deserves further testing as a spasmolytic.

Thymoxamine and intraocular pressure

Topical treatment with 1% thymoxamine produces in rabbit and human eyes a small but real miotic and tension-lowering effect. The latter is more evident using two different models of experimental ocular hypertension in rabbits. In human open-angle glaucoma eyes, tonographic measurements indicate that the outflow facility is left unchanged by the drug.

Effect of alpha receptor blocking drug, thymoxamine, on allergen induced bronchoconstriction in extrinsic asthma

In ten patients with extrinsic bronchial asthma, allergen provoked bronchospasm was significantly inhibited by the alpha receptor blocking drug thymoxamine given intravenously. In two of these patients thymoxamine by inhalation also effectively inhibited allergen induced bronchoconstriction. It is suggested that thymoxamine may be acting either by increasing intracellular levels of cyclic AMP and thus inhibiting mediator release following allergen challenge or by modifying the airways response to these mediators by altering the bronchomotor tone. The variable responses recorded after allergen challenge in presence of alpha blockade with thymoxamine suggests that the dominant effect is on the bronchomotor tone rather than the mediator release.