Overview
DESCRIPTION Phendimetrazine tartrate, as the dextro isomer, has the chemical name of (2S,3S)-3,4-Dimethyl-2-phenylmorpholine L-(+)-tartrate (1:1). The structural formula is: Phendimetrazine tartrate is a white, odorless crystalline powder. It is freely soluble in water; sparingly soluble in warm alcohol, insoluble in chloroform, acetone, ether and benzene.
Mechanism of Action
CLINICAL PHARMACOLOGY Phendimetrazine tartrate is a sympathomimetic amine with pharmacological activity similar to the prototype drugs of this class used in obesity, the amphetamines. Actions include central nervous system stimulation and elevation of blood pressure. Tachyphylaxis and tolerance have been demonstrated with all drugs of this class in which these phenomena have been looked for. Drugs of this class used in obesity are commonly known as “anorectics” or “anorexigenics”. It has not been established, however, that the action of such drugs in treating obesity is primarily one of appetite suppression. Other central nervous system actions or metabolic effects, may be involved for example.
Indications
- INDICATIONS AND USAGE Phendimetrazine tartrate is indicated in 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/m 2 or higher who have not responded to appropriate weight reducing regimen (diet and/or exercise) alone. Below is a chart of Body Mass Index (BMI) based on various heights and weights. BMI is calculated by taking the patient’s weight in kilograms (kg), divided by the patient’s height, in meters (m), squared.
Common Doses
- 35 mg
- 17.5 mg
Dosage
DOSAGE AND ADMINISTRATION Usual Adult Dosage: 1 tablet (35 mg) twice a day or three times a day one hour before meals. Dosage should be individualized to obtain an adequate response with the lowest effective dosage. In some cases, 1/2 tablet (17.5 mg) per dose may be adequate. Dosage should not exceed 2 tablets three times a day.
Contraindications
- CONTRAINDICATIONS Known hypersensitivity or idiosyncratic reactions to sympathomimetics. Advanced arteriosclerosis, symptomatic cardiovascular disease, moderate and severe hypertension, hyperthyroidism, and glaucoma. Highly nervous or agitated patients. Patients with a history of drug abuse. Patients taking other CNS stimulants, including monoamine oxidase inhibitors
Side Effects
- ADVERSE REACTIONS Cardiovascular: Palpitation, tachycardia, elevated blood pressure, ischemic events. Valvular heart disease associated with the use of some anorectic agents such as fenfluramine and dexfenfluramine, both independently and especially when used in combination with other anorectic drugs, have been reported. However, no case of this valvulopathy has been reported when phendimetrazine tartrate has been used alone. Central Nervous System: Overstimulation, restlessness, insomnia, agitation, flushing, tremor, sweating, dizziness, headache, psychotic state, blurring of vision.
Interactions
- Interactions Drug Interactions Efficacy of phendimetrazine tartrate with other anorectic agents has not been studied and the combined use may have the potential for serious cardiac problems. Drug/Laboratory Test Interactions Drug Interactions Efficacy of phendimetrazine tartrate with other anorectic agents has not been studied and the combined use may have the potential for serious cardiac problems.