Used as an adjunct to lifestyle changes and not intended to replace them.
Orlistat (Xenical) a commonly used medication to treat obesity.
Anti-obesity medication or weight loss drugs are all pharmacological agents that reduce or control weight.
These drugs alter weight regulation, by altering either appetite, or absorption of calories.
The main treatment modalities for overweight and obese individuals remain dieting and physical exercise.
Orlistat (Xenical) reduces intestinal fat absorption by inhibiting pancreatic lipase.
It is recommended that anti-obesity drugs only be prescribed for obesity where it is hoped that the benefits of the treatment outweigh its risks.
Orlistat gastrointestinal adverse effects are frequent, including flatulence, steatorrhea , and diarrhea, and may cause malabsorption of fat soluble vitamins.
Catecholamines and their derivatives, such as phentermine and other amphetamine-based drugs, are the main tools used for appetite suppression.
Catecholamines, and other classes of drugs such as anti-depressants and mood stabilizers have been anecdotally used for appetite suppression, such as bupropion and topiramate.
Orlistat (also known as Xenical and Alli) blocks fat breakdown and thereby prevents fat absorption.
Anorectics are primarily intended to suppress the appetite, but most of the drugs in this class also act as stimulants.
Orlistat reduces intestinal fat absorption by inhibiting pancreatic lipase.
Some side-effects: include frequent, oily bowel movements.
If fat in the diet is reduced, symptoms often improve.
Lorcaserin (Belviq) is associated with a modest average weight loss, and the most common side effects of the drug are considered benign.
Sibutramine an anorectic or appetite suppressant, reducing the desire to eat, has been withdrawn from the market.
Rimonabant (Acomplia) is a recently developed anti-obesity medication, is a cannabinoid (CB1) receptor antagonist that acts centrally on the brain thus decreasing appetite.
Rimonabant may also act peripherally by increasing thermogenesis and therefore increasing energy expenditure.
Due to safety concerns, primarily psychiatric in nature, the drug has not received approval in the United States.
The drug metformin can reduce weight, by limiting the amount of glucose that is produced by the liver as well as increases muscle consumption of glucose, and increases the body’s response to insulin.
Metformin is associated with approximately 3% weight loss in approximately 25 to 50% of participants achieve at least 5% weight loss.
Exenatide (Byetta) is a long-acting analogue of the hormone GLP-1, which the intestines secrete in response to the presence of food.
Exenatide delays gastric emptying and promotes a feeling of satiety.
Some obese people are deficient in GLP-1, and dieting reduces GLP-1 further.
Drawbacks of exenatide include that it must be injected subcutaneously twice daily, and that it causes severe nausea in some patients, especially when therapy is initiated.
Pramlintide (Symlin), a synthetic analogue of the hormone amylin, which is secreted by the pancreas in response to eating.
Amylin delays gastric emptying and promotes a feeling of satiety.
Many diabetics are deficient in Amylin.
Symlin is only approved to be used along with insulin by Type 1 and Type 2 diabetics.
Symlin must be injected at mealtimes.
The combination of phentermine and topiramate, brand name Qsymiais an obesity treatment complementary to a diet and exercise regimen.
Four sympathomimetic oral amines phentermine, diethylpropion, benheyamine, and phendimetrazone are FDA approved for short term use of 12 weeks.
These medications should be avoided in patients with coronary artery disease, hypertension, glaucoma, and substance use disorders.
Pnentermine is in an adrenergic drugs that reduces appetite and affects food intake, where the enhancement of norepinephrine release and blockade of norepinephrine reuptake.
There are concerns about long-term effects on the heart and blood vessels, mental health and cognitive side-effects.
Topiramate weight loss mechanism is unknown but may anlter appetite and decrease energy intake.
The combination of naltrexone and bupropion, brand name Contrave is another option.
Weight loss drugs associated with medical complications, such as fatal pulmonary hypertension and heart valve damage due to Redux and Fen-phen, and hemorrhagic stroke due phenylpropanolamine.
Agents that work as a laxative can cause the potassium level to drop, which may cause heart and/or muscle problems.
Orlistat, blocks absorption of dietary fats, and as a result may cause oily spotting bowel movements, oily stools, stomach pain, and flatulence.
Acarbose partially blocks absorption of carbohydrates in the small intestine, and produces similar side effects including stomach pain and flatulence.
Mechanisms prevent most monotherapies from producing sustained large amounts of weight loss.
Hypothesized that combinations of drugs may be more effective by targeting multiple pathways and possibly inhibiting feedback pathways that work to cause a plateau in weight loss.
Combination therapy clinical: Qsymia (topiramate + phentermine), Empatic (bupropion + zonisamide) and Contrave (bupropion + naltrexone).
GLP-1 receptor agonists mimic the effects of GLP-1.
After eating GLP-1 acts on the hypothalamus to suppress appetite, delay gastric emptying, increase glucose dependent insulin release, decrease glucagon secretion, and increase pancreatic beta cell growth: Semaglutide, Liraglutide.
Tirzepatide is a synthetic peptide with dual hormonal agonistic activity at the GLP-1 receptor, and additionally, at the glucose dependent insulinotropic polypeptide receptor.