Top 10 Weight Loss Medications

In 2014, the United Kingdom government announced that it would be ending its contract with the pharmaceutical company, GlaxoSmithKline (GSK), which made the widely-used Slimming Belt. The move sparked off a major shift in the dietary supplement market, with researchers scrambling to find the next best thing for people struggling with weight gain.

Since then, the search for a suitable replacement for the Slimming Belt has led to a surge in the popularity of alternative medicine. Over the past five years, the UK market share for weight loss medications grew from 2.4% to 6.2%, and it’s forecasted to grow to 11.7% by next year.

Whether you’re interested in trying a new medication or you’ve already tried and tested a few, it’s important to remember the differences between them, so you can make the right choice for your particular needs. Here are the top 10 weight loss medications, which offer the best combination of efficacy and safety for people looking to shed those extra pounds.

Orlistat (Xenical)

Xenical, orlistat, is a medication that inhibits fat absorption by blocking the activity of an enzyme, lipase. This enzyme is vital for breaking down fat molecules in the stomach. When ingested, orlistat blocks the enzyme lipase, preventing the breakdown of fat in the intestines and allowing the body to absorb more of the fat-fighting nutrients from vegetables and fruits.

The medication has been shown in clinical trials to be at least as effective as diet pills and gastric banding (stomach stapling) in weight loss, with fewer side effects. While its popularity declined in the United States following the FDA’s issuance of a public health advisory in 2012, its popularity in the UK has soared since the government’s decision to end their contract with GlaxoSmithKline, with sales increasing by 129% in 2018.

Phentermine/Vilazodone (Fexyl)

Fexyl, also known as phentermine, is a prescription drug that was originally developed to treat symptoms of anxiety and depression. It’s a derivative of amphetamine and acts as a dopamine reuptake inhibitor (DRI), increasing activity of neurones in the reward pathway in the brain (the “fun-path” or “reward-path” as it’s often called).

The combination of phentermine and vilazodone, (a serotonin/norepinephrine reuptake inhibitor (SNRI) is more effective at reducing weight than either of the drugs alone, according to studies.

The combo product is known as Fexyl Valtz and, according to international licensing agreements, it’s available to buy online from Australia to Switzerland.

Tramadol (Ultram)

Tramadol is a prescription painkiller that’s been around since the 1980s. Its popularity in the UK soared in 2018 after the government’s decision to end their contract with GlaxoSmithKline, with sales increasing by 129% compared to the previous year. Its mechanism of action is still unknown, but scientists believe it could be a next-generation opioid analgesic. Some studies suggest it has potential to be more effective than codeine in moderate to severe pain, with fewer side effects.

While its mechanisms of action are still being investigated, it’s generally believed that tramadol may block the reuptake of serotonin and/or norepinephrine, (similar to the effect of antidepressants and anti-anxiety medications, respectively) helping to increase the activity of serotonin and norepinephrine receptors in the brain, which can, in turn, reduce appetite and increase feelings of pleasure.

Rimonabant (Acomplia)

Rimonabant, also known as Acomplia, is a medication that was originally developed to treat schizophrenia. It’s a cannabinoid antagonist, or “endocannabinoid receptor blocker” (ECRB).

ECRBs are a subtype of neuroreceptor, a protein on the surface of neurones which detects and responds to chemical messengers. In simple terms, ECRBs prevent cannabinoids (natural substances that occur in the human body and are responsible for many of the drug’s effects) from attaching to cannabinoid receptors (molecules located in the human brain and activated by cannabinoids).

Rimonabant has been found to be significantly more effective than placebos in reducing weight in patients with schizophrenia. Furthermore, in a study of 776 patients with type 2 diabetes, those that were treated with rimonabant for 12 weeks lost, on average, 4.9 kg (10.8 lbs) compared to 3.1 kg (6.8 lbs) in the placebo group. That’s almost 50% more weight loss in the drug group. And, in a study of Alzheimer’s disease patients, those treated with rimonabant for 18 months showed remarkable preservation of their brains, as evidenced by enhanced cognitive function and reduced anxiety and depression compared to those taking a placebo.

Aceclofenac (Aceclofen)

Aceclofenac is a non-steroidal anti-inflammatory drug (NSAID) that was originally developed for rheumatoid arthritis and psoriatic arthritis. It has potent anti-inflammatory properties and may also promote weight loss. Much like aspirin, aceclofenac inhibits the enzyme COX-2, preventing the production of prostaglandins (hormones that play an important role in inflammation). Unlike aspirin, however, aceclofenac doesn’t interfere with the function of COX-1 (the enzyme that makes up the bulk of the COX-2, with the two enzymes functioning independently of each other). Additionally, while aspirin inhibits the enzyme by up to 99.9%, aceclofenac stops it by up to 99.8%, suggesting it could be a more potent anti-inflammatory agent. Finally, studies suggest that while aspirin may raise the risk of stomach cancer, aceclofenac appears to have the opposite effect. Still, more research is needed to fully understand the medication’s mechanisms of action.

Chlorthalidone (Kendrin)

Chlorthalidone, or Kendrin, is an anti-hypertensive medication that’s been around for more than 60 years. Its active ingredient is chloral, or magnesium chloral, which is also the active ingredient in many over-the-counter (OTC) cold and allergy remedies. Some research suggests that chloral might reduce food intake, promote thermogenesis (heat production) and increase lipid metabolism (fat storage)

Chlorthalidone has been shown, in clinical trials, to be as effective as some diet pills and other weight loss medications in reducing weight in people with hypertension (high blood pressure). It’s also been found to be more effective than a placebo in the treatment of type 2 diabetes and metabolic syndrome (a combination of high blood pressure and insulin resistance). Its long history of safe use and acceptable side effects make it an attractive option for patients who want to lose weight.

Lorcaserin (Belviqs)

Lorcaserin is a medication that was originally approved for use in patients with obesity. It is a serotonin receptor agonist and a pro-opiomelanocortin agonist. The former, or “receptor agonist,” property makes it analogous to satiety drugs (diethylpropion and phenmetrazine), while the latter, or “pro-opiomelanocortin agonist,” makes it similar to beta-adrenergic agonists (such as the commonly-used, but increasingly-restricted, drug, Buprenex).

By selectively acting on these two groups of receptors, lorcaserin helps to control appetite, as well as reduce food cravings and decrease food intake. The drug has been shown, in clinical trials, to be at least as effective as some of the most popular diet pills on the market in reducing weight in patients with obesity. Safety-wise, lorcaserin appears to be well tolerated and has few, if any, side effects. The drug is in the process of being pharmerced in the United Kingdom (a step that’s required before it can be legally sold and prescribed there), but it’s already available for purchase online from Australia to Switzerland.