Diethylpropion Generic Name & Formulations
Store at 20 to 25°C (68 to 77°F).
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 Dosage and Administration
25mg 3 times daily, 1 hr before meals, and in midevening for night hunger or one 75mg sustained-release tab daily in midmorning.
One 25mg 3 times daily, 1 hr before meals, and in midevening for night hunger if desired to overcome night hunger.
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.
Care should be taken in dose selection, and it may be useful to monitor renal function.
Pulmonary hypertension, advanced arteriosclerosis, hyperthyroidism, known hypersensitivity or idiosyncrasy to the sympathomimetic amines, glaucoma, severe hypertension.
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 Boxed Warnings
- 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.
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.
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.
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.
Rapidly absorbed from the GI tract after oral administration.
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.
- 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 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 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 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.