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Phentermine Dosage

Applies to the following strength(s): 30 mg ; 15 mg ; 37.5 mg ; 8 mg ; 18.75 mg ; resin 15 mg ; resin 30 mg

The information at Drugs.com is not a substitute for medical advice. Always consult your doctor or pharmacist.

Usual Adult Dose for:

Usual Pediatric Dose for:

Additional dosage information:

Usual Adult Dose for Obesity

8 mg orally 3 times a day 30 minutes before meals, OR
15 to 37.5 mg orally once a day before breakfast or 1 to 2 hours after breakfast.

Use: 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 in patients with an initial body mass index (BMI) of 30 kg/m2 or greater, or BMI of 27 kg/m2 or greater in the presence of other risk factors (e.g., controlled hypertension, diabetes, hyperlipidemia).

Usual Pediatric Dose for Obesity

Age 17 Years and Older:
8 mg orally 3 times a day 30 minutes before meals, OR
15 to 37.5 mg orally once a day before breakfast or 1 to 2 hours after breakfast.

Use: 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 in patients with an initial body mass index (BMI) of 30 kg/m2 or greater, or BMI of 27 kg/m2 or greater in the presence of other risk factors (e.g., controlled hypertension, diabetes, hyperlipidemia).

Renal Dose Adjustments

Use with caution; drug exposure increases may occur in those with renal impairment.

Liver Dose Adjustments

Data not available.

Dose Adjustments

Patients Not Requiring a Full Dose:
-Tablets are scored to facilitate administering half of the usual dose.
-Dosing Options: 4 mg orally 3 times a day 30 minutes before meals; 18.75 mg orally once a day before breakfast or 1 to 2 hours after breakfast; OR 18.75 mg orally 2 times a day.

Precautions

Safety and efficacy have not been established in patients younger than 17 years.

Consult WARNINGS section for additional precautions.

US Controlled Substance: Schedule IV

Dialysis

Data not available.

Other Comments

Administration Advice:
-Individualize dosage to obtain an adequate response with the lowest effective dose.
-Avoid late evening administration due to the possibility of resulting insomnia.

Storage Requirements: Store at 20 to 25 degrees Celsius and protect from moisture and light.

General: Consult the manufacturer product information on overdose management.

Monitoring: Development of new, unexplained symptoms of dyspnea, angina pectoris, syncope, or lower extremity edema (during treatment).

Patient Advice: Avoid activities that require mental alertness such as driving and operating machinery until you know how this drug affects you.

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