Information For Patients
Patients must be informed that
phentermine hydrochloride is a short-term (a few weeks) adjunct in a regimen of
weight reduction based on exercise, behavioral modification and caloric
restriction in the management of exogenous obesity, and that coadministration
of phentermine with other drugs for weight loss is not recommended (see INDICATIONS
AND USAGE and WARNINGS).
Patients must be instructed on
how much phentermine to take, and when and how to take it (see DOSAGE AND
Advise pregnant women and
nursing mothers not to use phentermine (see PRECAUTIONS).
Patients must be informed
about the risks of use of phentermine (including the risks discussed in
Warnings and Precautions), about the symptoms of potential adverse
reactions and when to contact a physician and/or take other action. The risks
include, but are not limited to:
- Development of primary pulmonary hypertension (see WARNINGS)
- Development of serious valvular heart disease (see WARNINGS)
- Effects on the ability to engage in potentially hazardous
tasks (see WARNINGS)
- The risk of an increase in blood pressure (see WARNINGS and ADVERSE REACTIONS)
- The risk of interactions (see CONTRAINDICATIONS, WARNINGS,
and DRUG INTERACTIONS)
The patients must also be informed about
- the potential for developing tolerance and actions if
they suspect developmentof tolerance (see WARNINGS) and
- the risk of dependence and the potential consequences of
abuse (see WARNINGS, Drug Abuse and Dependence, and OVERDOSAGE).
Tell patients to keep phentermine in a safe place to
prevent theft, accidental overdose, misuse or abuse. Selling or giving away
phentermine may harm others and is against the law.
Carcinogenesis, Mutagenesis, Impairment Of Fertility
Studies have not been performed with phentermine to
determine the potential for carcinogenesis, mutagenesis or impairment of
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.
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.
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.
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.
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