Lecture 24 Obesity Part 2 Flashcards
What are regulatory criteria regarding obesity pharmacotherapy?
agent must be studied in clinical trials of at least 1 year of duration,
agent must produce mean weight loss of >/= 5% compared to placebo or at least 5% weight loss in 35% of patients with this proportion being more than DOUBLE placebo,, agent should show improvement in obesity-related comorbidities
What are indications for obesity pharmacotherapy?
pt with BMI >/= 30 or >/= 27 with comorbidities associated with extra body fat (ex. DM, HTN, dyslipidemia, obstructive sleep apnea)
What are the approved medications in Canada for obesity?
orlistat, liraglutide, semaglutide, naltrexone/bupropion
What are contraindications for obesity pharmacotherapy?
pregnant or breastfeeding pt, pt trying to conceive
Orlistat for obesity (MOA, Dose, AE, Drug Intx)
MOA: selective inhibitor of pancreatic lipase, inhibits breakdown of dietary fat into absorbable FFAs ⇒ 30% of ingested TGs are excreted primarily in feces, creates caloric deficit, results in modest weight loss, DOESN’T TARGET APPETITE OR SATIETY MECHS (NO CENTRAL MOA),
Dose: 120 mg TID, admin during or up to one hour AFTER meals,
daily multivitamin also recommended when on this med, but separate admin by at least 2 hours or take at bedtime,
AE: GI, loose stools, oily spotting, flatulence with discharge, fecal urgency and increased defecation, decreased absorption of ADEK,
Drug Intx: levothyroxine, cyclosporine, anticonvulsants, oral anticoagulants (warfarin) due to decreased Vit K absorption
Naltrexone/bupropion for obesity (MOA, Dose, AE, Contra, Drug Intx)
MOA: first agent - opioid receptor antagonist, disrupts auto-inhibitory effect of endogenous opioid peptides to prolong appetite suppression and reduce cravings,
second agent - inhibits reuptake of DA and NE, induces satiety centrally, appetite suppression,
have synergistic effect and agents don’t cause significant reduction when used alone,
Dose: 8 mg/90 mg per tab ⇒ 1 tab QD F1W, increase by 1 tab each week until maintenance dose of 2 tabs BID (16 mg/180 mg BID),
AE: N/D/C, H/A, insomnia, dry mouth, dizziness, increased BP and HR,
Contraindications: uncontrolled HTN, concurrent use of MAOI, opioid use including tramadol, seizure disorders, anorexia, bulimia, abrupt discontinuation of alcohol or benzos or barbiturates or anti-epileptic meds,
Drug Intx: second agent inhibits 2D6 ⇒ effects SSRIs, BBs, type 1C antiarrhythmics, TCAs
GLP-1RAs for obesity (MOA, AE, Contra)
MOA: mimic this hormone secreted in small intestine in response to food intake ⇒ appetite suppression and reduced caloric intake via mod of neuronal pathways in hypothalamus (reduced cravings, delayed meal initiation, lower overall caloric intake),
delayed gastric emptying - early satiety which may contribute to decreased food intake,
also enhances insulin secretion and suppresses glucagon release, reduces hepatic fat accumulation (NAFLD),
AE: N/C/D/V, heartburn, titration may help with GI side effects,
increased risk of gallstones, pancreatitis,, rare/unknown: alopecia, suicide, suicidal ideation, self harm,
Contra: personal or FHx of medullary thyroid cancer, multiple endocrine neoplasia type 2 (MEN2), T1D
What are the different doses/escalations for GLP-1s?
Liraglutide (Saxenda) - 3.0 mg SC QD, initial dose of 0.6 mg with up-titration by 0.6 mg weekly until target,
Semaglutide (Wegovy) - 2.4 mg SC once weekly, initiate at 0.25 mg weekly titrating up as needed every 4 weeks to 0.5 ⇒ 1 ⇒ 1.7 ⇒ 2.4 mg,
Tirzepatide (Mounjaro, not approved yet for weight loss) - 2.5 mg SC once weekly, titrating by 2.5 mg up every 4 weeks ⇒ 5, 10, or 15 mg
What are ways to manage AEs of GLP-1RAs?
Improve Eating Habits - eat slowly, smaller portions, avoid lying down after meal, stop eating when feeling full, increasing meal frequency, avoid drinking using straw, eat without distractions and savour the food, avoid activity right after eating, avoid eating too close to bed,
Adapt Food Consumption - easy to digest food, low fat, use oven or griddle or boiling, increase fluids, avoid sweet meals, avoid dressings or spicy foods or canned food or sauces that aren’t home cooked
What are indications for bariatric surgery, and what types are there?
Indications: BMI of 35 who have at least one major obesity-related complication ⇒ T2DM, HTN, dyslipidemia, hypoventilation syndrome, debilitating arthritis, fatty liver, CAD, OSA,
BMI of 40 independent of presence of obesity-related complications,
BMI 30-35 who are refractory to non-surgical interventions,
Types: adjustable gastric banding, sleeve gastrectomy, gastric bypass, duodenal switch
What are AE and long term risks of bariatric surgery?
AE: dysphasia, V/C, dumping syndrome (food moves too quickly from stomach to small intestine after eating without being digested), increased bowel movements, bloating,
Long-Term Risks: GERD, Barrett’s esophagus, anastomotic ulcer, hernia, small bowel obstructions, weight regain, bone health, kidney stones, protein malnutrition, vitamin deficiency
What are some post-bariatric surgery health modifications?
low fat, moderate carb, high protein diet ⇒ minimum 60 g protein/day for LS/RYGB, minimum 80-120 g/day in duodenal switch,
minimal to no alcohol intake, physical activity (150-300 min/week), smoking cessation, cannabis (limit or avoid), no carbonated or caffeinated beverages
What are medications to avoid taking after bariatric surgery?
NSAIDs - especially after RYGB or DS due to risk of anastomotic ulcers,
DOACs - unpredictable absorption,
low dose ASA - for secondary prevention can continue but need PPI for protection,
oral contraceptives - may be less effective, alternative contraception methods preferred
What are some meds which may need to be altered due to bariatric surgery?
Diabetes meds: insulin and SUs should be adjusted due to improved insulin sensitivity,
Warfarin: requires dose reduction (>20%) with frequent INR,
BBs: hydrophilic options (ex. atenolol) are preferred,
Lipid-lowering: statin tx may require dose adjustments due to altered metabolism
What are recommended vitamin supplementation for patients who have had a bariatric surgery?
ALL INFO BELOW IS CENTERED AROUND A GASTRIC BAND AND SLEEVE GASTRECTOMY OPERATION (DIFFERENCES ARE NOTED FOR RYGB AND DS),
Multivitamin: 2 OTC complete ones everyday
Thiamine (B1): 12 mg/day (higher doses if at risk, RYGB and DS recommended for 3.4 mg/day and 50-100 for high risk)
Vitamin B12: 350-500 mcg/day (oral), nasal spray UD, or 1000 mcg/month IM/SC
Vitamin D: 3000 IU/day titrated to maintain 25(OH)D > 75 mmol/L (DS often requires higher doses of around 50000 IU 2-3 x per week)
Calcium: 1200-1500 mg/day (preferably citrate) (DS recommended 1800-2400 mg/day)
Iron: low risk - 18 mg/day
menstruating - 45-60 mg/day (take iron separate from calcium)
Zinc: 8-11 mg/day (DS recommended 16-22 mg/day)
Copper: 1 mg/day (DS recommended 2 mg/day)
Vitamin A: 5000-10000 IU/day (DS recommended 10000 IU)
Vitamin K: 90-120 mcg/day (DS recommended 300 mcg/day)
DS may also need Vitamin E supplement
Folic Acid: 400-800 mcg/day and 1000 mcg in pregnancy - for RYGB patient
