Obesity Medications

• Lipase inhibitor med info

  Orlistat (Xenical, Ali)

  • MOA: inhibit gastric and pancreatic lipase and reduces absorption of dietary fat by about 30%
  • AE: flatulence, oily spotting, fecal urgency/incontinence, bloating, and cramping all d/t malabsorption of fat
  • CI: chronic malabsorption syndromes, cholestasis, safety/efficacy not proven in pregnant/breastfeeding, hepatotoxicity
  • Pt. C: nonscheduled, associated w/ LDL reduction (double what's expected)
  • Use: approved for LONG term use (up to 4 years), about 2-3 kg weight loss
• GLP-1 RA med info

  Liraglutide, Semaglutide (Wegovy, Ozempic)

  • MOA: analogues of human GLP-1 that increase insulin secretion, decrease glucagon secretion, reduce gastric emptying, and increase satiety
  • AE: n/v, diarrhea or constipation, pancreatitis (rare) or kidney dysfunction (rare)
  • CI: gastroparesis, hx of pancreatitis, pt w/ MENS2, family hx of medullary thyroid carcinoma, hypersensitivity
  • Pt. C: expensive, liraglutide = avg 5.8 kg loss at 1 year, semaglutide = avg 15 kg loss over 68 weeks
  • Caution: can reduce rate of absorptionof drugs that require rapid absorption so separate by 1 hour
• GIP/GLP-1 RA med info

  Tirzepatide (Mounjaro)

  • MOA: agonist at BOT GIP and GLP-1 receptors resulting in same things as GLP-1 RA and may contribute to regulation of food intake
  • AE: same as GLP-1s
  • Pt. C: very expensive, avg 16-22 kg weight loss
  • Clinical: T2DM, chronic obesity
• Anorexiants (Sympathomimetics)

  Phentermine (Adipex P)

  • MOA: increase norepinephrine and dopamine release, lead to stimulation of CNS, BP elevation and appetite suppression
  • AE: dry mouth, HA, insomnia, constipation, increase HR and BP, pulm. HTN and valvular HD
  • CI: use of MAOI within 14 days, hx of CVD, HF, arrhythmias, stroke, pulm. HTN, glaucoma, hyperthyroidism, substance abuse, PREGNANCY
  • Pt.C: 3-4 kg loss, can have withdraw sx (fatigue, depression) if abrupt stop, tell pt to avoid caffeine or other CNS stimulants and report new angina, dysrhythmia, CVA, syncope, dyspnea or edema
• Phentermine/Topiramate ER info

  • MOA: phentermine = sympathomimetic effects, topiramate = unknown, effects on appetite suppression and satiety enhancement via neurotransmitter effects
  • AE: paresthesia, dry mouth, headache, insomnia (avoid evening dose), constipation, increased heart rate, increased BP, pulmonary HTN and valvular heart disease
  • CI: same as phentermine
  • Pt. C: avg 6.6-8.6 % loss after 1 year, renal and hepatic dose adjustments
  • Use: chronic mgmt of weight loss, start low and titrate up
• Naltrexone/Burpropion ER

  • MOA: affect two areas of brain that regulate food intake → hypothalamus (appetite regulation) and mesolimbic dopamine circuit (reward system); Naltrexone = opioid antagonist, Bupropion = dopamine and norepi reuptake inhibitor
  • AE: n/v, constipation, HA, dizzy, increased BP and HR
  • CI: buprop is a cYP2D6 inhibitor, uncontrolled HTN, seizure disorder, anorexia/bulimia, drug/alcohol withdrawal, chronic opioid use, MAOIs
  • BBW: suicidal thoughts and behaviors, neuropsychiatric reactions
  • Use: start low and icnrease dose, d/c if don't achieve 5% wt loss after 12 weeks