What appetite suppressant would you recommend for a healthy adult patient?

Recommended Appetite Suppressant for Healthy Adults

For a healthy adult patient seeking appetite suppression, GLP-1 receptor agonists (semaglutide 2.4 mg or liraglutide 3.0 mg) are the preferred first-line agents due to superior weight loss efficacy (8-20% body weight), favorable cardiovascular safety profiles, and lack of stimulant-related contraindications. 1

Primary Recommendation: GLP-1 Receptor Agonists

Semaglutide 2.4 mg (Wegovy)

• Produces the highest weight loss among FDA-approved medications, with mean weight reduction of approximately 15-17% at 68 weeks 1
• Administered as once-weekly subcutaneous injection 1
• Works by enhancing satiety and reducing appetite through GLP-1 receptor activation 1
• Particularly appropriate for patients reporting inadequate meal satiety 1

Liraglutide 3.0 mg (Saxenda)

• Achieves mean weight loss of 8.0% at 56 weeks 1
• Administered as daily subcutaneous injection with dose titration from 0.6 mg to 3.0 mg over 5 weeks 1
• Suitable for patients with prediabetes, impaired glucose tolerance, or those requiring concomitant psychiatric medications 1
• Avoid in patients with personal or family history of medullary thyroid carcinoma or multiple endocrine neoplasia syndrome type 2 1

Alternative Oral Agents (Second-Line Options)

Phentermine-Topiramate ER

• Most effective oral combination with 9.8-10.9% weight loss at 56 weeks 1
• Dose titration: start 3.75/23 mg daily for 2 weeks, increase to 7.5/46 mg, with further escalation to 15/92 mg as needed 1
• Particularly suitable for younger patients needing appetite suppression and those with comorbid migraines 1
• Contraindicated in patients with uncontrolled hypertension, active coronary disease, hyperthyroidism, glaucoma, anxiety, insomnia, history of nephrolithiasis, or recent MAOI use 1
• Requires pregnancy prevention due to teratogenic risk from topiramate component 1

Naltrexone-Bupropion ER (Contrave)

• Achieves 5.1-6.4% weight loss at 56 weeks 1
• Dose titration over 4 weeks to maintenance dose of 16/180 mg twice daily 1
• Ideal for patients describing food cravings, addictive eating behaviors, comorbid depression, or those attempting smoking cessation or alcohol reduction 1
• Neither a controlled substance nor injectable, offering convenience advantages 1
• Contraindicated in patients with uncontrolled hypertension, seizure history, eating disorders, recent MAOI use, or those requiring opioid medications 1
• Must be discontinued before procedures requiring opioid analgesia 1

Phentermine Monotherapy

• Produces 5.45-9.6% weight loss in clinical trials 1
• FDA-approved only for short-term use (12 weeks), though commonly prescribed off-label for longer durations with appropriate monitoring 2, 3, 4
• Typical dosing: 15-37.5 mg once daily in the morning 4
• Suitable for younger patients requiring appetite suppression without cardiovascular disease 1, 2
• Requires baseline and periodic monitoring of blood pressure and heart rate at every visit 2, 5, 3
• Absolute contraindications include history of cardiovascular disease (coronary artery disease, stroke, arrhythmias, heart failure), uncontrolled hypertension, hyperthyroidism, glaucoma, agitated states, drug abuse history, pregnancy, or current/recent MAOI use 1, 2, 4
• Discontinue if less than 5% weight loss after 12 weeks on maximum dose 2, 3

Agents to Avoid or Use With Caution

Lorcaserin

• Produces modest 4.5-5.8% weight loss 1
• Contraindicated in patients on other serotonergic medications or with known cardiac valvular disease 1

Orlistat

• Conditionally recommended AGAINST by recent AGA guidelines due to modest weight loss (2.8-5.6%) and frequent gastrointestinal adverse effects including flatulence, steatorrhea, and diarrhea 1
• May cause malabsorption of fat-soluble vitamins requiring supplementation 1
• Consider only when other medications are contraindicated, unavailable, or unaffordable 1

Clinical Decision Algorithm

1. First-line for most healthy adults: Prescribe GLP-1 receptor agonist (semaglutide 2.4 mg or liraglutide 3.0 mg) for superior efficacy and safety profile 1

2. If patient has needle aversion or prefers oral therapy: Consider phentermine-topiramate ER as most effective oral option 1

3. If patient has comorbid depression, food cravings, or attempting smoking/alcohol cessation: Consider naltrexone-bupropion ER 1

4. If patient has cardiovascular risk factors or psychiatric medication use: Avoid phentermine; use GLP-1 agonists or naltrexone-bupropion ER instead 1, 2, 5

5. If cost is prohibitive for newer agents: Consider phentermine monotherapy with intensive cardiovascular monitoring in patients without contraindications 2, 3

Critical Monitoring Requirements

For Phentermine

• Baseline blood pressure, heart rate, cardiovascular assessment, pregnancy screening, thyroid function, and screening for glaucoma, anxiety, and substance abuse history 2, 4
• Monitor blood pressure and heart rate at every visit 2, 5, 3
• Discontinue if inadequate response (less than 5% weight loss) after 12 weeks 2, 3

For All Appetite Suppressants

• All medications must be combined with lifestyle interventions including dietary counseling and physical activity 1, 4
• Assess response at 12 weeks; discontinue if inadequate weight loss 1, 2
• Never combine multiple appetite suppressants due to lack of safety and efficacy data 4

Common Pitfalls to Avoid

• Do not confuse phentermine monotherapy with the discontinued "fen-phen" combination—valvular heart disease and pulmonary hypertension risks were attributed to fenfluramine, not phentermine 2
• Do not prescribe appetite suppressants as monotherapy—they must be adjunctive to comprehensive lifestyle modification 1, 4
• Do not assume all patients are candidates for phentermine—carefully screen for cardiovascular contraindications 2, 4
• Do not use naltrexone-bupropion in patients requiring opioid therapy—it will precipitate withdrawal or reduce analgesic efficacy 1