WARNINGS
Included as part of the "PRECAUTIONS" Section
PRECAUTIONS
Coadministration With Other Drug Products For Weight Loss
ADIPEX-P® is indicated only as short-term (a few weeks ) monotherapy for the management of
exogenous obesity. The safety and efficacy of combination therapy with ADIPEX-P® and any
other drug products for weight loss including prescribed drugs, over-the-counter preparations,
and herbal products, or serotonergic agents such as selective serotonin reuptake inhibitors (e.g.,
fluoxetine, sertraline, fluvoxamine, paroxetine), have not been established. Therefore,
coadministration of ADIPEX-P® and these drug products is not recommended.
Primary Pulmonary Hypertension
Primary Pulmonary Hypertension (PPH) – a rare, frequently fatal disease of the lungs – has been
reported to occur in patients receiving a combination of phentermine with fenfluramine or
dexfenfluramine. The possibility of an association between PPH and the use of ADIPEX-P® alone
cannot be ruled out; there have been rare cases of PPH in patients who reportedly have taken
phentermine alone. The initial symptom of PPH is usually dyspnea. Other initial symptoms may include
angina pectoris, syncope or lower extremity edema. Patients should be advised to report immediately
any deterioration in exercise tolerance. Treatment should be discontinued in patients who develop new,
unexplained symptoms of dyspnea, angina pectoris, syncope or lower extremity edema, and patients
should be evaluated for the possible presence of pulmonary hypertension.
Valvular Heart Disease
Serious regurgitant cardiac valvular disease, primarily affecting the mitral, aortic and/or tricus pid
valves, has been reported in otherwise healthy persons who had taken a combination of
phentermine with fenfluramine or dexfenfluramine for weight loss. The possible role of
phentermine in the etiology of these valvulopathies has not been established and their course in
individuals after the drugs are stopped is not known. The possibility of an association between
valvular heart disease and the use of ADIPEX-P® alone cannot be ruled out; there have been rare
cases of valvular heart disease in patients who reportedly have taken phentermine alone.
Development Of Tolerance, Discontinuation In Case Of Tolerance
When tolerance to the anorectant effect develops, the recommended dose should not be exceeded in an
attempt to increase the effect; rather, the drug should be discontinued.
Effect On The Ability To Engage In Potentially Hazardous Tasks
ADIPEX-P® may impair the ability of the patient to engage in potentially hazardous activities such as
operating machinery or driving a motor vehicle; the patient should therefore be cautioned accordingly.
Risk Of Abuse And Dependence
ADIPEX-P® is related chemically and pharmacologically to amphetamine (d- and dll-amphetamine) and
to other related stimulant drugs that have been extensively abused. The possibility of abuse of
ADIPEX-P® should be kept in mind when evaluating the desirability of including a drug as part of a
weight reduction program. See Drug Abuse And Dependence and OVERDOSE.
The least amount feasible should be prescribed or dispensed at one time in order to minimize the
possibility of overdosage.
Usage With Alcohol
Concomitant use of alcohol with ADIPEX-P® may result in an adverse drug reaction.
Use In Patients With Hypertension
Use caution in prescribing ADIPEX-P® for patients with even mild hypertension (risk of increase in
blood pressure).
Use In Patients On Insulin Or Oral Hypoglycemic Medications For Diabetes Mellitus
A reduction in insulin or oral hypoglycemic medications in patients with diabetes mellitus may be
required.
Nonclinical Toxicology
Carcinogenesis, Mutagenesis, Impairment Of Fertility
Studies have not been performed with phentermine to determine the potential for carcinogenesis,
mutagenesis or impairment of fertility.
Use In Specific Populations
Pregnancy
Pregnancy Category X
ADIPEX-P® 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 ADIPEX-P® 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
Based on the reported excretion of phentermine in urine, exposure increases can be expected in patients
with renal impairment [see CLINICAL PHARMACOLOGY].
Use caution when administering ADIPEX-P® to patients with renal impairment. In patients with severe
renal impairment (eGFR 15 to 29 mL/min/1.73 m2 ), limit the dosage of ADIPEX-P® to 15 mg daily [see DOSAGE AND ADMINISTRATION]. ADIPEX-P® has not been studied in patients with eGFR less than 15
mL/min/1.73 m2, including end-stage renal disease requiring dialysis; avoid use in these populations.