Pharmacologic Profile

General Use

These agents are used in the management of exogenous obesity as part of a regimen including a reduced-calorie diet. They are especially useful in the presence of other risk factors including hypertension, diabetes, or dyslipidemias.

General Action and Information

Phentermine is an anorexiant designed to ↓ appetite via its action in the CNS. Orlistat is a lipase inhibitor that ↓ absorption of dietary fat.

Contraindications

None of these agents should be used during pregnancy or lactation. Phentermine should not be used in patients with severe hepatic or renal disease, uncontrolled hypertension, known HF, or cardiovascular disease. Orlistat should not be used in patients with chronic malabsorption.

Precautions

Phentermine should be used cautiously in patients with a history of seizures, or angle-closure glaucoma and in geriatric patients.

Interactions

Phentermine may have additive, adverse effects with CNS stimulants, some vascular headache suppressants, MAO inhibitors, and some opioids (concurrent use should be avoided). Orlistat ↓ absorption of some fat-soluble vitamins and beta-carotene.

Nursing Implications

Assessment

• Monitor weight and dietary intake prior to and periodically during therapy. Adjust concurrent medications (antihypertensives, antidiabetics, lipid-lowering agents) as needed.

Potential Nursing Diagnoses

• Disturbed body image (Indications)
• Imbalanced nutrition: more than body requirements (Indications)
• Deficient knowledge related to medication regimen (Patient/Family Teaching)

Implementation

Patient/Family Teaching

• Advise patient that regular physical activity, approved by healthcare professional, should be used in conjunction with medication and diet.

Evaluation/Desired Outcomes

• Slow, consistent weight loss when combined with a reduced-calorie diet.