Reviewing medications to aid in weight loss

This report gave an overview of oral medications to help in managing obesity. 

Obesity is a worldwide health issue. People with obesity are at increased risk of a variety of health conditions, including heart disease, type 2 diabetes (T2D), and several types of cancer.

Obesity is complex, and there are multiple causes. A system of hormones regulates hunger and metabolism based on the person’s genetics, changes in body weight, diet, and environment. The body responds to very restrictive diets and dramatic weight loss by conserving energy, which can contribute to rebound weight gain. Sustainable lifestyle changes can lead to a weight loss of up to 10% of body weight, in addition to other health benefits. These changes can include increasing vegetables and fiber, exercising, decreasing fried foods and sweets, and improving sleep hygiene. 

Medications can assist in weight loss. Some medications affect the way the brain and hormone system regulate hunger. Other medications alter the way the body processes food or blood glucose. This report gives an overview of the available options and the benefits and drawbacks of each.

Orlistat (Xenical, Alli) is a weight loss medication that alters the way the body digests fats. Orlistat prevents triglycerides (blood fats) from being broken down into fatty acids. This reduces the amount of triglycerides absorbed by the gut by 30%. Orlistat leads to an additional weight loss of 2.8% of body weight after 1 year compared to placebo (inactive pills). Side effects can include gassiness, oily stools, and abdominal pain.

Lorcaserin (Belviq) affects hormones and appetite. This medication mimics some of the effects of serotonin, a neurotransmitter (signal) in the brain. Lorcaserin alters the brain’s release of the POMC pre-hormone, which affects hunger and may also affect how the body processes glucose. Lorcaserin leads to an additional loss of 3% of body weight compared to placebo. In 2020, lorcaserin was withdrawn from the market in America and Korea due to a study that found it may increase cancer risk (7.7% vs. 7.1% cancer rates). 

Naltrexone/bupropion ER (NB; Contrave) affects the brain and hormones, reduces appetite, and reduces food cravings. Bupropion alters the pre-hormone POMC, leading to reduced appetite. Naltrexone alters the way the brain responds to the body’s own opioids, which influence pleasure and food cravings. NB leads to an additional loss of 4.6% of body weight compared to placebo after a year. Common side effects include nausea and vomiting. This medication may increase the risk of suicide for young patients with depression, and the risk of seizures.

Liraglutide (Victoza, Saxenda) mimics the GLP-1 hormone, leading to reduced appetite and better blood glucose control for patients with T2D. GLP-1 is released by the gut after eating. It primes the pancreas to release the hormone insulin, leading to better glucose control. GLP-1 also activates the pre-hormone POMC, which reduces appetite. Liraglutide leads to an additional loss of 5.4% of body weight compared to placebo. Common side effects include nausea and diarrhea. There is a risk of pancreatitis (inflamed pancreas).

Phentermine/topiramate ER (PT; Qsymia) acts on the brain, reduces appetite, and may alter taste. PT is the most effective weight loss medicine available and leads to an additional 6.6% reduction in body weight compared to placebo. Patients taking PT had significant improvements in blood pressure, glucose control, and cholesterol. Common side effects include dry mouth, constipation, and insomnia. PT should not be used by women who are or may become pregnant, as it can cause cleft palate (a split in the roof of the mouth) in the baby.

This review found that there are multiple medications that can assist with weight loss.

These are prescription medications and should only be prescribed by your doctor, who can take into consideration all the benefits and risks.