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Didrex® is a brand name for the generic medication benzphetamine, a central nervous system stimulant classified as a sympathomimetic amine. It is used as an appetite suppressant to help obese patients lose weight, to be used in conjunction with diet and exercise. This drug is intended for use on a short-term basis only, under the close supervision of a doctor. Didrex® also increases a person's blood pressure and heart rate.
This drug is typically only used for a few weeks, because it can cause life-threatening side effects and it may be habit-forming. It is essential for patients to follow dosing instructions carefully. Usually, Didrex® is taken one to three times daily. A normal dose for an adult or teenage patient is no more than 25 to 50 milligrams (mg). Patients should avoid abruptly discontinuing this drug, because it may cause withdrawal effects.
Didrex® may cause some side effects, which should be reported to the doctor if they persist or become bothersome. These can include insomnia, hyperactivity, and dizziness. Tremors, headaches, and dry mouth have also been reported. Some patients have experienced an upset stomach, nausea, and diarrhea, along with increased sweating.
More serious side effects require a doctor's immediate care. These can include hives, facial swelling, and problems breathing, which may be indicative of an allergic reaction. Shortness of breath, chest pain, and feeling faint may also occur. Some patients have reported rapid heartbeat, heart palpitations, and unusual thoughts or behaviors. It is also possible to experience hallucinations, uncontrollable anger, and uncontrollable muscle movements, as well as seizures, slurred speech, and buzzing in the ears.
Patients taking Didrex® must take precautions to avoid engaging in activities that can increase the risk of side effects. They should avoid drinking alcohol. Diet pills and other stimulants should also be avoided. Since insomnia can occur, patients are advised not to take a dose in the evening.
This medication is not intended for use by pregnant or breastfeeding women, because it can cause birth defects. Those who have a heart problem, high blood pressure, or coronary artery disease may be unable to use Didrex®. Glaucoma, an overactive thyroid, and a history of drug or alcohol abuse or the use of diet pills may also preclude a patient from using this drug.
Before taking Didrex®, patients must disclose all their other medications and supplements to avoid an interaction. Those who have used a monoamine oxidase inhibitor (MAOI) within 14 days of using this appetite suppressant are at the risk of life-threatening side effects. Didrex® may also be contraindicated for use with blood pressure drugs, antidepressants, and attention deficit hyperactivity disorder (ADHD) medications. Diabetes drugs, insulin, and ascorbic acid, such as vitamin C may also interact with this drug.