Diethylpropion Sustained-release Tabs

— THERAPEUTIC CATEGORIES —
  • Obesity

Diethylpropion Sustained-release Tabs Generic Name & Formulations

General Description

Diethylpropion HCl 75mg; sust rel tabs.

Pharmacological Class

Sympathomimetic.

See Also

How Supplied

Contact supplier.

Storage

Store at 20 to 25°C (68 to 77°F).

Diethylpropion Sustained-release Tabs Indications

Indications

For the management of exogenous obesity as a short-term adjunct (a few weeks) in a regimen of weight reduction based on caloric restriction in patients with an initial body mass index (BMI) of 30 kg/m2 or higher and who have not responded to appropriate weight reducing regimen (diet and/or exercise) alone. Indicated for use as monotherapy only.

Diethylpropion Sustained-release Tabs Dosage and Administration

Adult

25mg 3 times daily, 1 hr before meals, and in midevening for night hunger or one 75mg sustained-release tab daily in midmorning.

Adult

One extended-release 75 mg tablet daily, swallowed whole, in midmorning.

Continue treatment only if patient has satisfactory weight loss within the first 4 weeks of treatment (eg, weight loss of at least 4lbs, or as determined by the physician and patient).

Not recommended for patients who used any anorectic agents within the prior year.

Discontinue if tolerance to diethylpropion develops, do not exceed the recommended dosage.

Dispense the least amount feasible at one time in order to minimize the possibility of overdosage.

Children

Not recommended.

Elderly

Care should be taken in dose selection, and it may be useful to monitor renal function.

Diethylpropion Sustained-release Tabs Contraindications

Contraindications

Arteriosclerosis. Hypertension. Hyperthyroidism. Glaucoma. Agitation. Drug or alcohol abuse. During or within 14 days of MAOIs.

Contraindications

  • Pulmonary hypertension, advanced arteriosclerosis, hyperthyroidism, known hypersensitivity or idiosyncrasy to the sympathomimetic amines, glaucoma, severe hypertension.

  • Agitated states.

  • Patients with a history of drug abuse.

  • Use in combination with other anorectic agents is contraindicated.

  • During or within 14 days following the administration of monoamine oxidase inhibitors (MAOIs), hypertensive crises may result.

Diethylpropion Sustained-release Tabs Boxed Warnings

Not Applicable

Diethylpropion Sustained-release Tabs Warnings/Precautions

Warnings/Precautions

Discontinue after a few weeks as tolerance to anorectic effect occurs. Epilepsy. Cardiovascular disease. Arrhythmias. Diabetes. Prescribe limited supply to prevent overdose. Pregnancy (Cat.B). Nursing mothers.

Warnings/Precautions

Pulmonary hypertension

  • Use of anorectic agents, including diethylpropion, was associated with an increased risk of developing pulmonary hypertension in a case-control epidemiological study.
  • Use of anorectic agents for >3 months was associated with a 23-fold increase in the risk of developing pulmonary hypertension.
  • Discontinue diethylpropion if aggravation of exertional dyspnea, or unexplained symptoms of angina pectoris, syncope, or lower extremity edema suggest the possibility of occurrence of pulmonary hypertension.
  • Baseline cardiac evaluation should be considered to detect preexisting pulmonary hypertension prior to initiating diethylpropion.

Valvular heart disease

  • Anorectic agents such as fenfluramine and dexfenfluramine have been associated with valvular heart disease.
  • Valvulopathy has been very rarely reported with diethylpropion.
  • Baseline cardiac evaluation should be considered to detect preexisting valvular heart disease prior to initiating diethylpropion.
  • Diethylpropion is not recommended in patients with known heart murmur or valvular heart disease.
  • Echocardiogram during and after treatment could be useful for detecting any valvular disorders which may occur.

Diethylpropion may impair the ability to engage in potentially hazardous activities (eg, operating machinery or driving a motor vehicle. Advise patient to use caution accordingly.

Prolonged use of diethylpropion may induce dependence with withdrawal syndrome on cessation of therapy.

Use with caution in patients with hypertension or with symptomatic cardiovascular disease, including arrhythmias. Severe hypertension: not recommended.

Patients with seizure disorders: monitor patients as reports suggest diethylpropion may increase convulsions.

Discontinue diethylpropion if tolerance develops; do not exceed the recommended dose.

Pregnancy Considerations

  • Teratogenic Effects: Pregnancy Category B. No adequate and well-controlled studies in pregnant women. Spontaneous reports of congenital malformations have been recorded in humans, but no causal relationship to diethylpropion has been established. 

  • Non-Teratogenic Effects. Abuse of diethylpropion during pregnancy may result in withdrawal symptoms in the human neonate.

Nursing Mother Considerations

Caution should be exercised; diethylpropion and/or its metabolites have been shown to be excreted in human milk.

Pediatric Considerations

Safety and effectiveness in pediatric patients below the age of 16 have not been established. Not recommended for patients 16 years of age and younger.

Geriatric Considerations

Dose selection should be cautious, usually starting at the low end of the dosing range, reflecting the greater frequency of decreased hepatic, renal, or cardiac function, and of concomitant disease or other drug therapy.

Renal Impairment Considerations

Diethylpropion is known to be substantially excreted by the kidney, and the risk of toxic reactions to this drug may be greater in patients with impaired renal function.

Diethylpropion Sustained-release Tabs Pharmacokinetics

Absorption

Rapidly absorbed from the GI tract after oral administration.

Metabolism

Extensively metabolized through a complex pathway of biotransformation involving N-dealkylation and reduction.

Elimination

Diethylpropion and its metabolites are excreted mainly by the kidney. Plasma half-life of the aminoketone metabolites is estimated to be between 4 to 6 hours.

Diethylpropion Sustained-release Tabs Interactions

Interactions

Hypertensive crisis with MAOIs. Blocks guanethidine. Adverse reaction with alcohol. Arrhythmias may occur with general anesthetics. Antagonized by phenothiazines.

Interactions

  • Contraindicated with MAOIs as hypertension may result.
  • Should not be used in combination with other anorectic agents; potential for serious cardiac problems.
  • Adverse interactions with alcohol should be considered.
  • Antidiabetic drug requirements (eg., insulin) may be altered.
  • Arrhythmias possible with concomitant general anesthetics.
  • The pressor effects of diethylpropion and those of other drugs may be additive when the drugs are used concomitantly.
  • Diethylpropion may interfere with antihypertensive drugs (eg, guanethidine, a-methyldopa). 
  • Concurrent use of phenothiazines may antagonize the anorectic effect of diethylpropion.

Diethylpropion Sustained-release Tabs Adverse Reactions

Adverse Reactions

Abuse potential, impairment in hazardous activities, arrhythmias, hypertension, CNS overstimulation, psychosis, dry mouth, GI disturbances, urticaria, impotence, seizures, blood dyscrasias, dyspnea, hair loss, dysuria.

Adverse Reactions

  • Cardiovascular: Precordial pain, arrhythmia (including ventricular), ECG changes, tachycardia, elevation of blood pressure, palpitation and rare reports of pulmonary hypertension.
  • CNS: Increase in convulsive episodes in patients with seizure disorders has been reported; dyskinesia, blurred vision, overstimulation, nervousness, restlessness, dizziness, jitteriness, insomnia, anxiety, euphoria, depression, dysphoria, tremor, mydriasis, drowsiness, malaise, headache, and cerebrovascular accident.
  • Hallucinations have occurred rarely following high doses of the drug. Several cases of toxic psychosis have been reported following excessive use and some have been reported in which the recommended dose appears not to have been exceeded.
  • Gastrointestinal: Vomiting, diarrhea, abdominal discomfort, dryness of the mouth, unpleasant taste, nausea, constipation, other gastrointestinal disturbances.
  • Allergic: Urticaria, rash, ecchymosis, erythema.
  • Endocrine: Impotence, changes in libido, gynecomastia, menstrual upset.
  • Hematopoietic system: Bone marrow depression, agranulocytosis, leukopenia.
  • Miscellaneous: Dysuria, dyspnea, hair loss, muscle pain, increased sweating, and polyuria.

Diethylpropion Sustained-release Tabs Clinical Trials

Clinical Trials

Adult obese patients instructed in dietary management and treated with anorectic drugs lose more weight on the average than those treated with placebo and diet, as determined in relatively short-term clinical trials.

The magnitude of increased weight loss of drug-treated patients over placebo-treated patients averages some fraction of a pound a week.

The rate of weight loss is greatest in the first weeks of therapy for both drug and placebo patients and tends to decrease in succeeding weeks.

Diethylpropion hydrochloride extended release tablets, 75mg have not been shown superior in effectiveness to the same dosage of the immediate-release formulation (one 25 mg tablet 3 times daily).

Diethylpropion Sustained-release Tabs Note

Notes

Formerly known under the brand names Tenuate, Tepanil (tabs); Tenuate Dospan, Tepanil Ten-tab (SR tabs).

Diethylpropion Sustained-release Tabs Patient Counseling

Patient Counseling

Patients should be cautioned about concomitant use of alcohol or other CNS-active drugs and diethylpropion.

Patients should be advised to observe caution when driving or engaging in any potentially hazardous activity.