Which drugs are good for weight loss?

In the pursuit of weight loss, some individuals turn to medications to aid their efforts. While certain drugs can support weight loss, it's crucial to understand how they work, the potential side effects, and the overall health implications.

FDA-approved medications for obesity

Medications approved by the U.S. Food and Drug Administration (FDA) for the treatment of obesity work primarily by reducing appetite and increasing feelings of fullness. Currently approved medications include: 

  • Semaglutide (Ozempic, Rybelsus, Wegovy) 
  • Liraglutide (Saxenda) 
  • Phentermine-topiramate (Qsymia) 
  • Orlistat (Alli, Xenical) 
  • Naltrexone-bupropion (Contrave) 
  • Setmelanotide (Imcivree)

Semaglutide (Ozempic, Rybelsus, Wegovy)  

Semaglutide belongs to a class of medications called glucagon-like peptide 1 (GLP-1) receptor agonists. This drug mimics the action of GLP-1, a gastrointestinal hormone. When blood sugar levels start to rise after someone eats, this drug stimulates the body to produce more insulin. The extra insulin helps to lower blood sugar levels. 

Semaglutide was originally approved by the FDA to treat type 2 diabetes because of its ability to improve blood sugar. In addition to improving blood sugar, this drug also seems to help people lose weight. One of the effects is that it slows the emptying of the stomach, increasing feelings of fullness. Another reason GLP-1 agonists aid in weight loss is because of its impact on the brain's motivation and reward system, reducing appetite for food and beverages. In 2021, semaglutide was approved to treat obesity under the brand name Wegovy, administered as a weekly at-home injection. 

Liraglutide (Saxenda)  

Similarly to semaglutide, liraglutide is also a GLP-1 agonist medication that helps to control blood sugar levels. Liraglutide was originally approved by the FDA to treat type 2 diabetes. In 2014, it was approved to treat obesity under the brand name Saxenda. This medication is a once daily injection. Liraglutide, along with semaglutide, are considered first-line treatments for obesity, especially in people with type 2 diabetes. These drugs are also used to reduce risk of heart attack and stroke.

Phentermine-topiramate (Qsymia)  

Phentermine works by affecting the central nervous system, leading to appetite suppression and, consequently, weight loss. Phentermine stimulates the release of neurotransmitters like norepinephrine, which influence the brain's appetite control center. 

While these drugs can be effective in the short term, they are not without risks. Increased heart rate, elevated blood pressure, and insomnia are common side effects associated with central nervous system stimulants. It's crucial if you are considering these drugs to consult with a healthcare professional to assess the potential benefits and risks based on your specific health conditions.

It's important to note that, while phentermine is an FDA-approved drug, it is a controlled substance and so any phentermine-containing product cannot be prescribed via a telehealth provider.

Orlistat (Alli, Xenical)  

Orlistat is available in pill form as a prescription medicine (Xenical) and as a reduced-strength, nonprescription medicine (Alli). It works by preventing your body’s absorption of dietary fats, thus reducing the total amount of calories your body retains. 

Orlistat can help with weight loss and improve blood pressure and blood fat levels. But it’s not as effective as GLP-1 agonists or phentermine-topiramate. It also frequently causes gastrointestinal side effects such as gas, oily spotting and loose stools. Following a low-fat diet helps reduce these side effects. 

Orlistat should not be used if you’re pregnant or you have chronic malabsorption issues. In rare cases, people have had serious liver injury while taking orlistat. But researchers haven't found that the drug causes liver injuries. 

Naltrexone-bupropion (Contrave)  

This medicine, which comes in extended-release pill form, contains a combination of naltrexone, an opiate-antagonist drug that’s used to treat addiction, and bupropion, an antidepressant that’s used to treat depression and help people quit smoking. The combination of drugs acts on the brain to promote feelings of fullness and control cravings. 

Naltrexone-bupropion may be a good option for people who want to lose weight and quit smoking. 

Like all antidepressants, bupropion carries a warning about suicide risk. Since naltrexone-bupropion can raise blood pressure, you’ll need to check your blood pressure regularly at the start of treatment. Common side effects include nausea, headache, and constipation.

Setmelanotide (Imcivree)  

Setmelanotide is a targeted drug made specifically for people with obesity related to a few rare genetic conditions: Bardet-Biedl syndrome (BBS) and pro-opiomelanocortin (POMC), proprotein convertase subtilisin/kexin type 1 (PCSK1), or leptin receptor (LEPR) deficiency. These inherited conditions tend to cause severe obesity. The medication isn’t used in people who don’t have these conditions. 

Short-term weight loss and long-term considerations 

Many drugs that promote weight loss may be effective in the short term, but sustaining these results over the long term can be challenging. Additionally, the initial weight loss may include water weight and muscle mass, rather than a reduction in fat tissue. 

It's essential to approach weight loss with realistic expectations and consider implementing sustainable lifestyle changes such as a balanced diet and regular exercise. Relying solely on medications without addressing underlying habits may lead to the regain of lost weight once the drugs are discontinued. 

Impact on eating habits and health problems 

Some weight-loss drugs influence eating habits by reducing appetite or altering taste perceptions. While this may aid in weight loss, it's crucial to monitor any changes in nutritional intake and ensure that you are still receiving essential nutrients. 

Moreover, certain drugs may exacerbate existing health problems or pose risks for those with specific conditions. People with high blood pressure should exercise caution when considering the use of weight-loss drugs. This is because certain weight-loss drugs have the potential to increase blood pressure and lead to heart problems.

Risk of substance abuse

The potential for substance abuse is a significant concern when using weight -oss drugs, especially those with stimulant properties. Some individuals may be tempted to exceed recommended dosages in the pursuit of faster results, increasing the risk of addiction and severe side effects.  

By exceeding prescribed dosages some may experience overdose side effects associated with weight-loss drugs such as hypoglycemia, gastrointestinal distress, or pancreatitis.

It’s essential to follow a diet and exercise program 

While certain weight-management drugs may assist people in losing weight, it's essential to approach their use with caution. Short-term benefits must be weighed against potential side effects and long-term health implications.  

You can avoid, or minimize, many common side effects by working closely with your prescribing provider to ensure you take the correct dose of medication, are eating a well-balanced diet and drinking enough water. 

A comprehensive weight-loss program, like the Mayo Clinic Diet, which includes lifestyle modifications, a specialized eating and exercise plan is crucial for achieving sustainable and healthy weight loss.

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