Increased risk in esophageal obstruction with slow-release medications

Although medication-induced (pill) esophagitis has been recognized for a long time, little data are available on the risk of recently introduced slow-release medications. These formulations may have an obstructive capability (undissolved medication blocking an obstructed lumen) or may cause tissue irritation (continuous leakage from a slowly disintegrating pill). We observed a patient with esophageal carcinoma who developed complete obstruction when three Procardia XL (nifedipine) extended-release tablets blocked the narrowed lumen. An intact Procardia XL tablet and a washed shell as a control were implanted subcutaneously in a rat. The intact pill produced a large inflammatory mass: in contrast, no inflammatory response was noted at the control site implanted with a washed shell. In vitro testing of seven different slow-release medications revealed a wide difference in their solubility at a neutral pH and in gastric juice of pH 1.8 (simulation of esophageal or gastric environment). Theolair-SR (anhydrous theophylline, sustained-release) tablets had the highest obstructive, but no irritating potential. Cardizem SR (diltiazem hydrochloride) sustained-release capsules dissolved promptly without obstructive potential. Adalat CC (nifedipine) extended-release tablets also dissolved early at both pH values. Cardizem CD (diltiazem hydrochloride) extended-release capsules and Calan SR (verapamil hydrochloride) sustained-release oral caplets disintegrated into granules that had a low obstructive potential, but their prolonged presence increased the risk of tissue irritation. Ecotrin (enteric-coated aspirin) tablets had a high obstructive and no irritating potential in the first 24 hours, after which they disintegrated and directly contacted the tissue. Procardia XL extended-release tablets had an insoluble shell that continued to leak a tissue-irritating content even after 48 hours, generating a prolonged obstructive and irritating condition. In conclusion, slow-release medications greatly increase the risk of esophageal injury. Their obstructive and tissue-irritating potentials differ widely. Slow-release formulations should be contraindicated in patients who have obstructive esophageal and gastric disorders.

Therapy of angina pectoris with long-acting nitrates: which agent and when?

Nitroglycerin and the long-acting nitrates are effective antianginal agents that have been used in clinical medicine for over 100 years. These drugs are reliable, safe, familiar to clinicians, inexpensive, and easy to use. Side effects are limited to headache and postural hypotensive symptoms. Nitrate tolerance or attenuation, -ie, loss of, or decrease in, nitrate efficacy with repeated dosing-is common and represents the major drawback to chronic therapy. Carefully designed dosing regimens and/or appropriate use of nitrate formulations (to include a nitrate-free period each day) will decrease or eliminate the problem of nitrate tolerance. In head-on comparative studies, nitrates appear to be as effective as beta-blockers or calcium channel blockers in the monotherapy of chronic angina. Ideal patient characteristics for nitrate therapy include: predictably favourable response of chest pain to sublingual nitroglycerin; angina episodes suggestive of coronary vaso-constriction or spasm; left ventricular systolic dysfunction; symptoms of congestive heart failure (systolic or diastolic dysfunction).

Self assembling nanostructures for sustained ophthalmic drug delivery

Nanopseudolatex was prepared for sustained ophthalmic delivery. It was prepared by a solvent injection method without the use of any stabilizer. The acrylate copolymers Eudragit RLPM and RSPM were used as carrier materials. Their formation was confirmed by electron microscopy. The system was extensively characterized for particle size, viscosity, sedimentation volume, encapsulation efficiency, in vitro release profile and pharmacodynamic properties. The particle size was found to be stirring rate dependent above the injection rate of 1 ml/min. Only at slow stirring rates it was temperature dependent. There was no sedimentation for about 60 d. The viscosity was 23-27 cps which was particle size dependent. The results show an excellent encapsulation efficiency of about 94-98%. Release studies showed slow and consistent drug release from the formulation. However, Eudragit RSPM showed comparatively longer release than Eudragit RLPM nanosuspensions. Using this method we have developed a new formulation of diclofenac diethyl ammonium which showed increased therapeutic efficacy as compared with eye drops.

Colonic medication bezoar from extended-release nifedipine and procainamide

We report an unusual case of a primary colonic bezoar composed of extended-release formulations of nifedipine and procainamide. Although these bezoars are rare, the increasingly frequent application of extended-release delivery systems to other commonly prescribed medications may increase the incidence of such bezoars in vulnerable patients. Clinicians should be aware of this potential problem when prescribing these medications, and have a high index of suspicion when painful or refractory constipation occurs.

Translating safety, efficacy and compliance into economic value for controlled release dosage forms

Advanced controlled release (CR) dosage forms are relative newcomers to pharmaceutical markets, and few studies relate their efficacy, safety or compliance benefits to economic value. This literature review was undertaken to assess the cost effectiveness of CR dosage forms using such measures as purchase costs, total treatment costs, and economic value of improved therapeutic outcomes compared with those with non-CR dosage forms. Three therapeutic areas were examined: cardiovascular therapy, pain management and estrogen replacement therapy. In cardiovascular therapy, prescription costs of sustained release (SR) verapamil were significantly higher than for conventional release verapamil. However, these were more than offset by lower physician, hospital and laboratory expenditures for the SR group, in whom compliance was superior. Similarly, patients receiving SR diltiazem had better prescription refill compliance than those using a conventional formulation of the drug, as well as significantly lower aggregate healthcare costs during a 1-year study period. These lower costs with both SR verapamil and diltiazem may relate to better compliance. CR nifedipine has lower daily acquisition costs than the conventional form, simplifies the dosage regimen to once daily, extends the indications of the drug to hypertension as well as angina, and reduces vasodilatory adverse effects by reducing peak plasma drug concentrations and the postdose rate of increase in concentration. Compared with oral clonidine given twice daily, transdermal clonidine, given once weekly, had higher purchase costs, but was associated with improved compliance, reduced adverse effects (due to control of plasma concentrations), and lower nondrug health costs, such as physician, hospital and laboratory costs. Lower costs were also found for once daily oral formulations of various antihypertensives, suggesting that the economics of both types of CR dosage forms related to compliance. CR metoprolol 50 or 100mg and conventional release atenolol 50mg, each given once daily, provided effective beta1-adrenoceptor blockade. The conventional formulation caused deterioration in the sense of well-being that was temporally associated with sharp peaking of its plasma concentrations. Such peaking did not occur with either dose of CR metoprolol, nor did any deterioration in the sense of well-being. Transdermal nitroglycerin (glyceryl trinitrate), compared with long-acting oral nitrates, improved quality of life (QOL) {despite a higher incidence of some adverse effects, such as headache, dizziness and skin irritation}. Furthermore, in some studies, this formulation reduced angina attacks, sublingual nitroglycerin use, and hospitalisation or emergency room use. Cost comparisons between transdermal products favoured those that have superior adhesion.(ABSTRACT TRUNCATED AT 400 WORDS)

Novel oral drug formulations. Their potential in modulating adverse effects

The rationale for specialised oral formulations of drugs include prolongation of effect for increased patient convenience and reduction of adverse effects through lowered peak plasma concentrations. Local and systemic adverse effects due to high concentrations of drug can be minimised by the use of controlled release delivery systems. Local effects in the gastrointestinal (GI) tract from the release of irritant drug molecules can also be reduced, but the gastric damage caused by nonsteroidal anti-inflammatory drugs (NSAIDs) is only partially relieved by formulation approaches because of the involvement of systemic factors in the aetiology of GI adverse events. The advantages for each drug class must be examined. Newer dosage forms include: (i) osmotic pumps and zero order kinetics systems to control the release rate of the drug; (ii) bioadhesive systems and gastric retention devices to control GI transit; (iii) bioerodible hydrogels; (iv) molecular carrier systems (e.g. cyclodextrin-encapsulated drugs) to modulate local toxicity in the GI tract; (v) externally activated systems; and (vi) colloidal systems such as liposomes and microspheres. There is evidence for improved tolerability for a variety of drugs administered in novel delivery systems. However, the evidence for improved tolerability is complicated by the potential bias in adverse reaction reporting systems, and a lack of studies directly comparing conventional and modified release preparations. The technology now available to produce delivery systems which not only release drugs in a controlled and predetermined fashion, but which can also target to regions of the GI tract such as the colon, should allow greater control of therapy and potentially might minimise patient variables. However, the problem of variable GI transit times still eludes solution. Systems which rely on time to release drug might be more vulnerable to patient-to-patient variability than those which respond to local environments. The effect of food intake is more apparent on single-unit, nondisintegrating dosage forms, although of course none so far are immune from influence. The risk of new adverse effects resulting from such positional therapy with novel delivery devices must be considered. Understanding the mechanisms of induction of individual adverse effects can lead to advances in modes of delivery to decrease the potential for adverse reactions and events while maintaining therapeutic efficacy. Increased compliance can led to increased therapeutic control and hence safety. Each system has to be considered on its merits. No generalisations can be made, although invariably the modulation of high peak plasma concentrations diminishes adverse effects due to rapid absorption.

The effect of non-depot ACTH(1-24) on infantile spasms

However, side-effects such as severe infections, hypertension and electrolyte imbalance have been found, assumed to be related to hypercortisolism induced by chronic ACTH treatment. The authors treated 18 patients with infantile spasms with non-depot ACTH(1-24). The therapeutic effect of non-depot ACTH was comparable to that of depot ACTH, with no severe bacterial infection or sepsis. The incidence of hypertension was significantly lower in the non-depot ACTH group, and persistent hypercortisolaemia was not found. Non-depot ACTH(1-24) appears to be as effective as ACTH(1-24) depot therapy in the treatment of infantile spasms, and its side-effects are mild. It would appear that the effect of non-depot ACTH is not mediated by hypercortisolism, but by a direct neurotropic effect on the brain.

Oral mesalamine (Pentasa) as maintenance treatment in Crohn's disease: a multicenter placebo-controlled study. The Groupe d'Etudes Thérapeutiques des Affections Inflammatoires Digestives (GETAID)

BACKGROUND

Mesalamine provides a new therapeutic approach in treating Crohn's disease.

METHODS

To assess the efficacy and safety of slow-release mesalamine (Pentasa; Ferring AS, Vanløse, Denmark) in maintaining remission in Crohn's disease, 161 patients with inactive disease were randomized to receive either Pentasa (2 g/day) or placebo in a 2-year double-blind, multicenter trial. Two strata were defined according to the duration of their remission: < 3 months (n = 64) or 3-24 months (n = 97), presumed to be high and a low relapse risk strata, respectively.

RESULTS

The probability of relapse was higher in the short-remission placebo group than in the three other groups (P < 0.003), showing there was a significant benefit from Pentasa in the high relapse risk stratum. In this stratum, the 2-year ongoing remission rate was of 29% +/- 9% and 45% +/- 11% (mean +/- SD) in the placebo and Pentasa groups, respectively. The incidences of side effects were similar in both groups.

CONCLUSIONS

Pentasa (2 g/day for 2 years) is a safe and effective maintenance treatment for Crohn's disease when given within 3 months of achieving remission.

[Fever caused by neuroleptics]

If fever arises in patients using neuroleptic drugs, it is possible that the fever is an adverse reaction to the drug. Two cases are reported of patients who developed fever to neuroleptic agents. In one patient it probably concerned a reaction to the solvent of the sustained-action preparation of the drug. The other patient developed fever probably as part of the neuroleptic malignant syndrome.

A case of ulcerative colitis induced by oral ferrous sulfate

We report a case of ulcerative colitis (UC) in a 15 year old female undergoing treatment for anemia with oral ferrous sulfate. We suggest that the oral ferrous sulfate initiated the typical symptoms of UC in this case. This case is the first clinical report to our knowledge supporting the 'iron-catalysed oxidant-mediated ischemic injury theory' of UC.

The long-term growth and development of children exposed to Depo-Provera during pregnancy or lactation

Children exposed to the injectable contraceptive Depo-Provera (DMPA) during pregnancy (N = 1,207), and/or during breastfeeding (N = 1,215) were exposures during pregnancy or breastfeeding. Weights and heights were measured for all children, and information on signs of puberty obtained for children aged ten and over. Cross-sectional weights and heights by age of DMPA-exposed children were similar to those for controls. Children with DMPA exposure during pregnancy and lactation had an increased risk of suboptimal growth in height, defined as less than two Z scores on NCHS standards (RR = 1.4, 95% CI 1.2-1.8). However, after adjustment for socioeconomic factors by multiple logistic regression, there was no increased risk of impaired growth among the DMPA-exposed children (RR = 1.1, 95% CI 0.8 - 1.6). With the exception of a delay in onset of reported pubic hair growth among DMPA-exposed girls, there were no significant effects on attainment of puberty. We conclude that use of DMPA during pregnancy or breastfeeding does not adversely affect the long-term growth and development of children.

Nifedipine GITS (gastrointestinal therapeutic system) bezoar

In a patient with a gastroplasty, gastric outlet obstruction developed after the dosage of nifedipine GITS (gastrointestinal therapeutic system) was increased from 30 to 60 mg/d. The hard, insoluble shell for this extended-release tablet appears causative.

Bone density in women receiving depot medroxyprogesterone acetate for contraception

OBJECTIVE

To determine if the use of the injectable contraceptive depot medroxyprogesterone (DMPA), which reduces ovarian oestrogen production, is associated with changes in bone density.

DESIGN

Population study. DMPA users were compared with two control groups selected from larger population studies and individually matched for several putative determinants of bone density (age, race, body mass index, and years of oestrogen deficiency). Controls and DMPA users were matched without prior knowledge of their bone density measurements.

SETTING

Teaching hospital and community family planning clinics.

SUBJECTS

30 current users of DMPA with a minimum five years' previous use, 30 premenopausal controls, and 30 postmenopausal controls.

MAIN OUTCOME MEASURE

Lumbar spine and femoral neck bone mineral density assessed by dual energy x ray absorptiometry.

RESULTS

Compared with premenopausal controls matched for age, race, and body mass index, DMPA users had significantly reduced bone density in the lumbar spine (mean difference 7.5% (95% confidence interval 1.9% to 13.1%), p = 0.002) and in the femoral neck (6.6%, (0.8% to 12.3%), p = 0.007). Compared with postmenopausal controls matched for body mass index and duration of oestrogen deficiency, DMPA users had greater bone density in the lumbar spine (8.9% (4.3% to 13.5%), p = 0.001), but in the femoral neck the difference in bone density was less (4.0% (-0.4% to 8.5%), p = 0.04).

CONCLUSIONS

Women using DMPA have bone density values intermediate between those of normal premenopausal and postmenopausal controls; thus, the degree of oestrogen deficiency induced by DMPA may have an adverse effect on bone density.

[Priapism secondary to phenothiazines]

We report two cases of priapism in patients previously treated with neuroleptic agents. None of these patients had a previous history of urological or hematological disorders. These two patients warranted emergency treatment by punction-aspiration of the corpora cavernosa and posterior cavernospongiosa shunt. The foregoing approach achieved penile detumescence in both cases. Excellent results were achieved relative to erectile function in one patient. Although the mechanism responsible for phenothiazine-induce priapism has as yet not been elucidated, it has been suggested that this might be due to adrenergic block which directly inhibits the sympathetic impulse of detumescence.

Unilateral mydriasis caused by transdermal scopolamine

Contamination of the eye after handling of a transdermal scopolamine patch may cause accidental mydriasis. A simple office test is discussed to identify this pharmacologic blockade and thereby avoid an extensive neurologic workup.

[Surfen allergy causing insulin depot S hypersensitivity]

Allergic cutaneous reaction developed in 3 patients upon the use of Insulin-depot-S-Richter injections. Allergological examinations confirmed the eliciting role of surfen, the material being responsible for the depot effect. The patients were treated thereafter with surfen-free insulin. The authors deal also with the side-effects of insulin treatment as well as with certain forms of insulin allergy.

Pill-induced esophageal strictures: clinical features and risk factors for development

Clinical data from five subjects with pill-induced esophageal strictures and from the English-language literature on pill-induced esophageal damage were reviewed to determine risk factors for stricture development and to characterize this complication. Including our five cases, 195 patients with pill-induced damage and 39 patients with pill-induced strictures have been reported to date. Seventy-eight percent of the strictures were located in the proximal or mid-esophagus. Potassium chloride or quinidine preparations were incriminated in 60% of cases and were more likely to produce stricture than other medications commonly associated with esophageal damage (e.g., tetracycline). Older age, male gender, left atrial enlargement, ingestion of sustained-release formulations, and prior esophageal structural abnormality were all more commonly present in the subset with strictures (p less than 0.05 for each), even after appropriately controlling for medication. A logistic regression analysis revealed that older age and ingestion of sustained-release formulations were the most significant independent factors associated with stricture development (p less than 0.0001 for each). These findings indicate that stricture formation from pill-induced esophageal damage is dependent upon host-related factors as well as the caustic nature of the pill.

Sustained-release dosage forms

Transdermal drug delivery provides an effective and advantageous alternative to the oral delivery of therapeutic agents. Currently, many other drugs are being evaluated for transdermal delivery including testosterone, fentanyl, nicotine and timolol. They offer the promise of simplified dosage regimens, enhanced compliance, reduced side effects and improved therapy of disease.

[Respiratory depression following controlled-release morphine sulfate tablets]

Controlled release morphine sulfate (MS Contin) is a relatively new oral preparation for the relief of chronic severe (cancer) pain. We describe a patient with severe neuralgia who experienced respiratory depression after ingestion of one single dose of morphine sulfate (20 mg). Administration of nalorphine chloride resulted in instant normalisation of respiratory function. This case illustrates respiratory depression as an adverse effect of MS Contin.

Clinical comparison of systemic methylprednisolone acetate versus topical budesonide in patients with seasonal allergic rhinitis

Thirty patients with seasonal allergic rhinitis entered a double blind study comparing budesonide (nasal spray, 400 micrograms/d) and i.m. injection of 80 mg methylprednisolone acetate. Symptoms were assessed over a "run in" period of 3-7 days followed by a treatment period of 3 weeks. Pollen counts were evaluated daily. Both the systemic and topical corticosteroid treatment resulted in a significant improvement of nasal and ocular symptoms and were accompanied by reduced antihistamine intake. A comparison of the two treatments in relation to the pollen count yielded statistically significantly fewer nasal symptoms, such as itching, secretion, and sneezing in the budesonide-treated group. Nasal blockage and ocular symptoms remained unchanged, but the use of eyedrops was significantly reduced in the methylprednisolone-treated group. Side effects of both treatments were mild and the incidence negligible. Methylprednisolone-treated patients had a significantly lower cortisol value after 7 days but still had a normal response to ACTH-stimulation. We conclude that the acute symptoms of allergic rhinitis are at least as well ameliorated by regular topical application of budesonide as by a single injection of methylprednisolone acetate. The accompanying allergic conjunctivitis may require additional treatment.

Unusual treatment response of a severe dystonia to diphenhydramine

A 27-year-old man was admitted to the emergency department with a fluphenazine decanoate-induced dystonia. He was treated with 125 mg diphenhydramine IV in four doses and 2 mg benztropine IM. A fluctuating response was observed before continued remission of the dystonia. Possible reasons for variable patient responses to diphenhydramine are discussed.

Jejunal perforation possibly induced by slow-release potassium in a patient with Crohn's disease

A case of small bowel ulceration and perforation possibly due to therapy with Klotrix in a patient with Crohn's disease is presented. Following emergent surgery with creation of a diverting loop jejunostomy, subsequent reestablishment of intestinal continuity was carried out with excellent clinical results. Gastrointestinal mucosal lesions possibly due to wax-matrix potassium chloride preparations are reviewed.

Efficacy and tolerability of sustained-release clomipramine (Anafranil SR) in the treatment of phobias: a comparison with the conventional formulation of clomipramine (Anafranil)

This multicentre double-blind trial in general practice compared the efficacy and tolerability of the sustained-release formulation of clomipramine (Anafranil SR) with its conventional formulation (Anafranil) in the treatment of phobias. Patients were allocated at random to receive clomipramine 75 mg once daily as either the sustained-release or conventional formulation for 11 weeks following a 1-week dosage build-up period. Analysis of results from forty-six patients showed that the sustained release formulation of clomipramine 75 mg was as effective as the conventional formulation of clomipramine 75 mg in improving symptoms of phobia as assessed by a phobia inventory and global evaluation. Unwanted effects attributable to therapy were similar in both treatment groups but there were fewer withdrawals due to unwanted effects of the sustained release formulation of clomipramine 75 mg. It was concluded that the sustained-release formulation of clomipramine does offer advantages for patients requiring 75 mg clomipramine daily.

Skin irritation caused by transdermal drug delivery systems during long-term (5 days) application

We have studied the skin irritation produced by the prolonged application of transdermal therapeutic systems. The systems were applied to the skin of the back of male volunteers for 120 hours, and sweat accumulation and bacterial growth were studied. In some cases hydrogel discs were attached to the systems. The results showed that sweat accumulation contributed more to the skin irritation than the bacterial overgrowth. The incorporation of hydrogels in the transdermal delivery system may help to reduce skin irritation by absorbing water.

Sclerosing granuloma after short-term administration of depot-insulin Hoechst. Case report and a review of the literature

A 41-year-old male diabetic patient is described who exhibited firm infiltrative lesions on the abdomen and both buttocks after six injections of Depot-Insulin Hoechst. Initially there were no indications of an allergic or infectious origin. Histologic examination showed a sclerosing granuloma, suggesting a foreign body reaction. Oily substances could not be detected in a skin lesion or in the contents remaining in the insulin bottle. Skin tests suggested an allergic reaction to surfen. This side effect of insulin must be very rare. We could find only one report in the literature describing similar cases; no case was found in the files of Hoechst Limited. Data from literature concerning reactions to Depot-Insulin Hoechst and to surfen, one of its components, are reviewed.

Comparison of Theolair SR and Theo-Dur tablets

The effects of administration of single doses of 10 mg/kg of two sustained release theophylline preparations were compared in a double-blind, crossover study in eight asthmatic children. Serum theophylline concentrations were maintained well for 8-10 hours after administration of Theolair SR and 10 and 12 hours after administration of single doses of Theo-Dur.

Comparison of the incidence and severity of extrapyramidal side effects with fluphenazine enanthate and fluphenazine decanoate

Forty-nine schizophrenic outpatients stabilized on oral antipsychotic medication and procyclidine received 12.5 mg or 18.75 mg of fluphenazine enanthate or fluphenazine decanoate and were examined for extrapyramidal side effects one and two weeks later. Extrapyramidal side effects were present in 30 patients (61%) but were clinically significant in only 11 (22%). Fluphenazine enanthate produced more clinically significant extrapyramidal symptoms, particularly akathisia, than did fluphenazine decanoate.

Bilateral retinal artery and choriocapillaris occlusion following the injection of long-acting corticosteroid suspensions in combination with other drugs: I. Clinical studies

Two well-documented cases of bilateral retinal artery and choriocapillaris occlusions with blindness following head and neck soft-tissue injection with methylprednisolone acetate in combination with lidocaine, epinephrine, or penicillin are reported. One case had only a unilateral injection. The acute observations included hazy sensorium, superior gaze palsy, pupillary abnormalities, and conjunctival hemorrhages with edema. Follow-up changes showed marked visual loss, constricted visual fields, optic nerve pallor, vascular attenuation, and chorioretinal atrophy. The literature is reviewed, and possible causes are discussed.

Bilateral retinal artery and choriocapillaris occlusion following the injection of long-acting corticosteroid suspensions in combination with other drugs: II. Animal experimental studies

An experimental dog model was used to reproduce the clinical picture of bilateral arteriole and choriocapillaris occlusion from a unilateral intracarotid injection of long-acting corticosteroids combined with other drugs including lidocaine, epinephrine, and penicillin. All five known long-acting corticosteroids, when combined with 1:1000,000 epinephrine, elicited vasoconstriction followed by dilatation of the retinal vessels with particulate material occlusion of the retinal vessels and choriocapillaris associated with small retinal hemorrhages. The fluorescein picture is described. The particles were identified by polarization as the long-acting corticosteroid.