Obesity Drug Summary

Drug	Dosage	Remarks
Amfepramone (Diethylpropion HCl)1	Immediate-release: 25 mg PO 8 hourly Extended-release: 75 mg PO 24 hourly	Adverse Reactions CV effects (tachycardia, palpitation, hypertension, pulmonary hypertension); CNS effects (restlessness, dizziness, insomnia, euphoria, tremor, dysphoria); GI effects (dry mouth, unpleasant taste in mouth, anorexia, constipation); Other effects (changes in libido, gynecomastia, muscle pain, hair loss, polyuria) Prolonged use may result in pharmacological tolerance, dependence and withdrawal symptoms on cessation of therapy Special Instructions Immediate-release: Administer 1 hour before meals; may also administer 1 tablet mid-evening to overcome night hunger Extended-release: Administer once daily, mid-morning Contraindicated in patients with hypersensitivity or idiosyncrasy to sympathomimetic amines, with advanced arteriosclerosis, severe hypertension, pulmonary hypertension, hyperthyroidism, glaucoma, agitated states, history of drug abuse, concomitant use or within 14 days following MAO inhibitor therapy Use with caution in patients with seizures, psychiatric illness, DM, hypertension, symptomatic CV disease, renal and hepatic impairment
Phentermine	HCl: 8 mg PO 8 hourly or 15-40 mg PO 24 hourly at breakfast Ion-exchange resin complex: 15-30 mg PO 24 hourly in the morning	Adverse Reactions CV effects (tachycardia, palpitation, hypertension and pulmonary hypertension); CNS effects (restlessness, dizziness, insomnia, euphoria, tremor, dysphoria); GI effects (dry mouth, unpleasant taste, anorexia, constipation); Other effects (changes in libido, micturition disturbances) Prolonged use may result in pharmacological tolerance, dependence and withdrawal symptoms and more rarely to severe psychotic disorders in predisposed patients Special Instructions HCl: Administer 24 hourly before breakfast or 1-2 hour after breakfast Ion-exchange resin complex: Should be taken with food, at breakfast; avoid taking near bedtime Intermittent dosing, treatment period of several weeks followed by similar-length non-treatment period Contraindicated in patients with hypersensitivity or idiosyncrasy to sympathomimetic amines, with advanced arteriosclerosis, severe hypertension, pulmonary hypertension, hyperthyroidism, glaucoma, agitated states or a history of psychiatric illness, history of drug abuse, concomitant use or within 14 days following MAO inhibitor therapy Use with caution in patients with CVD, mild hypertension, DM, seizure disorders, renal impairment, on concomitant therapy with psychotropic drugs
Sibutramine HCl	Initial dose: 10 mg PO 24 hourly May increase to 15 mg PO 24 hourly after 4 weeks Max dose: 15 mg/day	Adverse Reactions GI effects (dry mouth, constipation, nausea/vomiting, dyspepsia, gastritis, taste perversion); CNS effects (insomnia, headache, dizziness, nervousness, anxiety, depression, somnolence, paresthesia); Other effects (anorexia, back pain, flu syndrome, palpitation, myalgia, arthralgia, rhinitis, rash, dysmenorrhea, UTI) Special Instructions Administer 24 hourly at any time, independent of meals May give 5 mg to patients who cannot tolerate the 10 mg dose Contraindicated in patients with severe renal or hepatic impairment, major eating disorder, inadequately controlled hypertension, history of coronary artery disease, CHF, arrhythmias, stroke Use with caution in patients with mild to moderate hepatic or renal impairment, narrow-angle glaucoma, seizure disorder, those at risk of bleeding events
Glucagon-Like Peptide-1 (GLP-1) Receptor Agonists
Liraglutide	Initial dose: 0.6 mg SC 24 hourly x 1 week May increase by 0.6 mg/day at weekly intervals to Max dose: 3 mg/day	Adverse Reactions GI effects (nausea/vomiting, diarrhea, constipation, dyspepsia, gastroesophageal reflux, acute pancreatitis); CNS effects (fatigue, dizziness, headache); Other effects (rash, hypersensitivity reactions, increased heart rate, hypoglycemia) Special Instructions Administer 24 hourly at any time, independent of meals Contraindicated in patients with personal history or family history of medullary thyroid cancer, in patients with multiple endocrine neoplasia syndrome type 2, in patients with active suicidal ideation Use with caution in patients with hepatic or renal impairment, history of pancreatitis, cholelithiasis and/or alcohol abuse Discontinue treatment if patient does not lose at least 4% of body weight after 16 weeks of therapy
Semaglutide	Initial dose: 0.25 mg SC once weekly x 4 weeks May increase the dose in 4-week intervals to Max dose: 2.4 mg once weekly	Adverse Reactions GI effects (nausea/vomiting, diarrhea, constipation, abdominal pain/distension, dyspepsia, gastroenteritis, GERD); CNS effects (headache, dizziness); Other effects (hypoglycemia in patients with type 2 diabetes, fatigue) Special Instructions Administer on the same day each week, at any time of day, independent of meals Contraindicated in patients with personal history or family history of medullary thyroid cancer, patients with multiple endocrine neoplasia syndrome type 2 Use with caution in patients with cholelithiasis, risk of hypoglycemia, renal impairment, hypersensitivity reactions, history of pancreatitis or diabetic retinopathy Monitor blood glucose in patients with type 2 diabetes before starting and during Semaglutide treatment; also monitor heart rate, renal function and for depression or suicidal thoughts
GLP-1 Receptor & Glucose-dependent Insulinotropic Polypeptide (GIP) Receptor Agonist
Tirzepatide	Initial dose: 2.5 mg SC once weekly After 4 weeks, increase to 5 mg SC once weekly May increase dose in 2.5 mg increments after at least 4 weeks on the current dose Max dose: 15 mg once weekly	Adverse Reactions GI effects (nausea/vomiting, constipation, diarrhea, decreased appetite, dyspepsia, abdominal pain, GERD); Other effects (injection site reactions, fatigue, hair loss, eructation, hypersensitivity reactions) Special Instructions Administer at any time of the day once weekly, with or without meals Avoid use in patients with severe GI disease Contraindicated in patients with personal or family history of medullary thyroid cancer or in patients with multiple endocrine neoplasia syndrome type 2 Use with caution in patients with acute kidney injury, gallbladder disease or diabetic retinopathy Discontinue immediately if pancreatitis or hypersensitivity reactions are suspected or if depression or suicidal thoughts develop
Combination Anti-obesity Agents
Naltrexone HCl/Bupropion HCl	Available dose: Naltrexone HCl 8 mg/Bupropion HCl 90 mg tab Week 1: 1 tab in the morning and none in the evening Week 2: 1 tab in the morning and 1 tab in the evening Week 3: 2 tabs in the morning and 1 tab in the evening Week 4 - onward: 2 tabs in the morning and 2 tabs in the evening	Adverse Reactions GI effects (nausea/vomiting, constipation, dry mouth, diarrhea); CNS effects (headache, dizziness, insomnia, suicidal behavior and ideation, neuropsychiatric symptoms, seizures); Other effects (angle-closure glaucoma, allergic reactions, increase in BP and heart rate) Special Instructions Contraindicated in patients with uncontrolled hypertension, seizure disorders, anorexia nervosa or bulimia, or those undergoing abrupt discontinuation of alcohol, benzodiazepines, barbiturates, and antiepileptic drugs; use of other Bupropion-containing products, chronic opioid use, during or within 14 days of taking MAO inhibitors Use with caution in patients with suicidal behavior and ideation, hepatotoxicity, angle-closure glaucoma Monitor BP and heart rate in all patients, blood glucose and for depression or suicidal thoughts Minimize seizure risk by following recommended dosing schedule and avoiding concomitant high-fat meal
Phentermine/Topiramate	Available doses: Phentermine 3.75 mg/Topiramate 23 mg cap, Phentermine 7.5 mg/Topiramate 46 mg cap, Phentermine 11.25 mg/Topiramate 69 mg cap, Phentermine 15 mg/Topiramate 92 mg cap Initial dose: Phentermine 3.75 mg/Topiramate 23 mg PO 24 hourly in the morning for 14 days Recommended dose: Phentermine 7.5 mg/Topiramate 46 mg PO 24 hourly Titration dose: Phentermine 11.25 mg/Topiramate 69 mg PO 24 hourly for 14 days Max dose: Phentermine 15 mg/Topiramate 92 mg per day	Adverse Reactions CV effect (increased heart rate); GI effects (dysgeusia, constipation, dry mouth); CNS effects (suicidal behavior and ideation, cognitive impairment, mood changes, insomnia, dizziness); Other effects (metabolic acidosis, acute closed-angle glaucoma) Special Instructions Administer in the morning with or without food; avoid late evening doses because of possibility of insomnia Discontinue or increase dose if weight loss of 3% after 12 weeks of treatment is not achieved with 7.5/46 mg combination Discontinue treatment if patient does not lose 5% of body weight after 12 weeks of therapy with maximum dose Monitor electrolytes; monitor for anxiety, depression, memory problems Contraindicated in pregnant women and sexually active women of childbearing age, in patients with glaucoma or hyperthyroidism

¹Combination with vitamins is available. Please see the latest MIMS for specific formulations and prescribing information.

Drug	Dosage	Remarks
Orlistat	Patient with BMI ≥28 kg/m2 irrespective of any risk factors: 60 mg PO 8 hourly Patient with BMI ≥30 kg/m2 or ≥27 kg/m2 with associated risk factors: 120 mg PO with each main meal	Adverse Reactions Adverse effects typically occur at the beginning of treatment and decrease with continued use especially if recommended diet is followed GI effects (oily spotting from rectum, flatus with discharge, fecal urgency, oily stools, oil evacuation, increase in defecation and fecal incontinence); Severe liver injury has rarely occurred Special Instructions Administer immediately before, during or up to 1 hour after each main meal If meal is missed or contains no fat, Orlistat dose should be skipped If patient does not lose 5% of body weight after 12 weeks of therapy discontinue treatment Use of a multivitamin may be recommended to patient to avoid loss of fat-soluble vitamins Should be taken at least 2 hours after Orlistat or at bedtime Contraindicated in patients with chronic malabsorption syndrome or cholestasis

Drug	Dosage	Remarks
Alfadex (α-cyclodextrine)	2,000 mg PO 8 hourly	Special Instructions May cause bloating and flatulence Contraindicated in patients with hypersensitivity, low fat diet program