tensive crisis.
Alcohol
Concomitant use of alcohol with phentermine may result in an adverse drug reaction.
Insulin and Oral Hypoglycemic Medications
Requirements may be altered (see WARNINGS)
Adrenergic Neuron Blocking Drugs
Phentermine may decrease the hypotensive effect of adrenergic neuron blocking drugs.
Carcinogenesis, Mutagenesis, Impairment of Fertility
Studies have not been performed with phentermine to determine the potential for carcinogenesis, mutagenesis or impairment of fertility.
Pregnancy
Pregnancy Category X
Phentermine is contraindicated during pregnancy because weight loss offers no potential benefit to a pregnant woman and may result in fetal harm. A minimum weight gain, and no weight loss, is currently recommended for all pregnant women, including those who are already overweight or obese, due to obligatory weight gain that occurs in maternal tissues during pregnancy. Phentermine has pharmacologic activity similar to amphetamine (d- and dll-amphetamine) (see CLINICAL PHARMACOLOGY ). Animal reproduction studies have not been conducted with phentermine. If this drug is used during pregnancy, or if the patient becomes pregnant while taking this drug, the patient should be apprised of the potential hazard to a fetus.
Nursing Mothers
It is not known if phentermine is excreted in human milk; however, other amphetamines are present in human milk. Because of the potential for serious adverse reactions in nursing infants, a decision should be made whether to discontinue nursing or to discontinue the drug, taking into account the importance of the drug to the mother.
Pediatric Use
Safety and effectiveness in pediatric patients have not been established. Because pediatric obesity is a chronic condition requiring long-term treatment, the use of this product, approved for short-term therapy, is not recommended.
Geriatric Use
In general, dose selection for an elderly patient 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.
This drug 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. Because elderly patients are more likely to have decreased renal function, care should be taken in dose selection, and it may be useful to monitor renal function.
Renal Impairment
Phentermine was not studied in patients with renal impairment. Based on the reported excretion of phentermine in urine, exposure increases can be expected in patients with renal impairment. Use caution when administering phentermine to patients with renal impairment (see CLINICAL PHARMACOLOGY).
ADVERSE REACTIONS
The following adverse reactions are described, or described in greater detail, in other sections:
- Primary pulmonary hypertension (see WARNINGS)
- Valvular heart disease (see WARNINGS)
- Effect on the ability to engage in potentially hazardous tasks (see WARNINGS)
- Withdrawal effects following prolonged high dosage administration (see DRUG ABUSE AND
DEPENDENCE)
The following adverse reactions to phentermine have been identified:
Cardiovascular
Primary pulmonary hypertension and/or regurgitant cardiac valvular disease, palpitation, tachycardia, elevation of blood pressure, ischemic events.
Central Nervous System
Overstimulation, rest |
