Drugs- Obesity Flashcards
list 4 sympathomimetic amines for obesity
Benzphtamine
Diethylpropion
Phendimetrazine
Phentermine
orlistat
lipase inhibitor
phentermine/topiramate ER
sympathomimetic amine/antiepileptic combo
lorcaserin
serotonin receptor agonist
bupropion/naltrexone
antidepressant/opioid antagonist combo
Liraglutide
GLP-1 agonist
treatment for severe binge eating disorder
lisdexamfetamine (vyvanse)
a modified amphetamine medication primarily indicated for the treatment of ADHD.
overweight BMI ? obese? candiate for surgery
• BMI between 25 and 29.9 kg/m2 are considered overweight; BMI> 30 considered obese; BMI > 40 is a candidate for surgery..
what are problems with pharm agents for weight loss
• Some drugs have received FDA approval for weight loss, but adherence is poor, adverse effects are common, and patients usually regain the lost weight when the drug is stopped.
by doing what with diet, how can pt’s lose weight
- Adults can lose 1-2 lbs per week by consuming 500-1000 fewer calories per day.
- Several recent clinical trials comparing diets with the same degree of caloric restriction but composed of differing macronutrient composition, i.e., differences in protein, fat, carbohydrates, showed no significant differences in weight loss.
- Diets with low-fat versus low-carbohydrate content resulted in no differences in fat mass or lean mass at 6 months and no difference in amount of weight loss at 12 months (15-20 lbs).
- Patients on a diet can lose 5% of their body weight over the first 6 months, but over 2-3 years often return to baseline.
what helps besides dieting alone lose weight
life coach
pharm for obesity should be conserved for what pt’s
• Pharmacotherapy should be reserved for patients with a BMI>30 or BMI>27 with a weight-related comorbidity such as hypertension, dyslipidemia, or diabetes.
sympathomimetic amines
MOA?
use?
how long can you use them?
- Sympathomimetic amines (mimic sympathetic nervous system agonists) are mostly structurally and functionally related to amphetamines. They work by releasing NE or preventing its neuronal reuptake. [Think methamphetamine].
- These drugs suppress appetite.
- These drugs are only approved for short-term use (weeks).
ADR’s of sympathomimetic amines
- All of these drugs are controlled substances and must be prescribed carefully.
- All these drugs can increase heart rate, raise blood pressure, and cause nervousness and insomnia.
phentermine /topiramate ER (Qysmia)
MOA
should we be using this drug?
sympathomimetic amine/antiepileptic combo
• Phentermine is a sympathomimetic amine and topiramate (Topamax) is used to treat epilepsy and migraine. Phentermine is FDA-approved for short-term treatment of obesity. Topiramate was observed in clinical trials (unrelated to obesity) to cause significant weight loss. The combination was recently (2013) FDA-approved for treatment of obesity.
schedule IV
• In clinical trials, Qsymia was effective in producing dose-dependent weight loss (6-13 kg over 56 weeks). It also was effective in maintaining weight loss over 2 years.
- This is arguably the most efficacious weight loss drug studied so far. But do the math! The best clinical trial results for this drug report that 66.7% of patients achieved > 5% weight loss after 56 weeks of treatment at the highest dose. Average beginning baseline weight was 118 kg (~260 lbs). So, 5% of 260 lbs is 13 lbs. Average weight loss on the drug was 12.6 kg (~28 lbs). Conclusion: the average patient went from 260 lbs to 232 lbs. That is significantly better than placebo (1.9 kg weight loss; 17.3% of patients > 5% weight loss), but is it a sufficient clinical endpoint?
- Qsymia has troublesome side effects. The discontinuation rate during the trials was about 40%. Qsymia is contraindicated during pregnancy and is available only through a restricted access program designed to prevent fetal exposure to the drug.
when should you discontinue use of Qsymia and how should you do this
• If >5% weight loss is not achieved after 12 weeks at maximum dose, the drug should be gradually discontinued; abrupt discontinuation of topiramate can cause seizures even in patients with no history of epilepsy.
ADR’s of Phentermine/Topiramate ER (Qsymia)
• Adverse effects include dry mouth, paresthesia, constipation, weird taste, and insomnia. This drug is contraindicated for use during pregnancy.
Orlistat (Xenical, Alli)
lipase inhibitor
- It is a pancreatic and gastric lipase inhibitor that decreases the absorption of fat from the GI tract.
- Used as an adjunct to diet, it is modestly effective in increasing weight loss (about 3kg more than patients taking placebo).
ADR’s of Orlistat
• Adverse effects of Orlistat limit its use. Flatulence with discharge, oily spotting, and fecal urgency occur predominantly after high-fat indiscretions and are associated with a high incidence of drug discontinuation.
CI in pregnancy
Lorcaserin (belvig)
Serotonin receptor agonist
- Lorcaserin is a new drug (2013); it is a selective serotonin 2C agonist that suppresses appetite.
- It is a schedule IV controlled substance; it is only modestly effective for weight loss, but is generally well tolerated.
- About 50% of patients taking the drug in clinical trials lost > 5% of their initial body weight; the average placebo-corrected weight loss after 1 year of use has been 3 kg (6.6 lbs). Patients who continued on lorcaserin regained about 25% of their initial weight loss in the second year.
when should you stop taking lorcaserin
• Patients that fail to lose > 5% of their baseline weight by 12 weeks should stop taking lorcaserin.
ADR’s of lorcaserin
• Adverse effects of lorcaserin include headache, nausea, and dizziness. Drug discontinuation during clinical trials was about 35-50%. Lorcaserin is contraindicated for use during pregnancy and should not be administered to patients also taking MAO inhibitors, SSRIs, or SNRIs ***
Bupropion/naltrexone (Contrave)
Antidepressant/Opioid Antagonist Combination
Bupropion is an appetite suppressant
Naltrexone opioid receptor antagonist
- The combination of bupropion + naltrexone (Contrave) has recently (2014) been approved for weight loss. It is not a controlled substance.
- Bupropion is an appetite suppressant and naltrexone potentiates that effect.
- In four clinical trials Contrave was associated with > 5% weight loss in 39-66% of patients after 56 weeks. Placebo-corrected weight loss at the end of 56 weeks was 4-5 kg (8.8 -11 lbs).
- If weight loss of > 5% is not achieved after 12 weeks, the drug should gradually be discontinued.
ADR’s of bupropion/naltrexone (Contrave)
• Adverse Effects: include nausea (the major reason for discontinuation) vomiting; headache, constipation, dizziness, and dry mouth.
Serious neuropsychiatric reactions have been reported with the use of bupropion for smoking cessation.
Other adverse effects have been reported. Use of Contrave during pregnancy is contraindicated.
