Apetamin Pills and Syrup for Weight Gain: Uses, Side Effects, and Legality

Apetamin for weight gain

Verywell / Alexandra Shytsman

Most health and fitness articles you see probably talk about weight loss versus weight gain. That’s no surprise, because millions of people in the U.S. try to lose weight each year. In fact, nearly half of all American adults tried to lose weight between 2013 and 2016, with an estimated 45 million Americans going on a diet each year—and spending a collective 33 billion dollars on weight loss products each year.

On the flip side, some people actually struggle to gain weight. This happens for various reasons. Some people are genetically just very thin; some people battle genetic or autoimmune diseases that make it hard to put on weight; some people have a low appetite or disordered eating that leads to low food intake; and some people simply want to put on muscle

A recent trend in the weight gain industry had people turning to an illicit supplement called apetamin. Banned from sale in the U.S., consumers are forced to purchase apetamin from small online websites or social media. In this article, learn how apetamin works for weight gain, as well as why it’s illegal and side effects to look out for.

What Is Apetamin?

Apetamin is a vitamin supplement used for weight gain. According to manufacturing labels and a product list from the company who developed apetamin (TIL Healthcare), apetamin syrup contains some combination of a prescription-only medication called cyproheptadine hydrochloride, vitamins, and amino acids (namely lysine). TIL Healthcare also has a number of other appetite stimulant products that contain cyproheptadine hydrochloride.

This combination of lysine, vitamins, and cyproheptadine hydrochloride is said to act as an appetite stimulant and increase the amount of food you can eat in a day. However, neither vitamins nor amino acids are known to increase appetite. Cyproheptadine hydrochloride is an antihistamine (a medicine that alleviates allergy symptoms) that has increased appetite listed as a known side effect. 

How Does Apetamin Work? 

Consumers believe that apetamin promotes weight gain because of its active ingredient of cyproheptadine hydrochloride. This powerful antihistamine has been used as an appetite stimulant in malnourished children and people with chronic diseases, such as cystic fibrosis.

Researchers and doctors aren’t entirely sure why cyproheptadine hydrochloride stimulates appetite, but a few possible scenarios do exist. 

For example, cyproheptadine hydrochloride may increase levels of a hormone called insulin-like growth factor (IFG-1) in children who are underweight. This hormone has been linked to weight gain in underweight children.

Cyproheptadine hydrochloride may also interfere with your hypothalamus, the small section of your brain that regulates appetite, cravings, food consumption, and many hormones.

L-lysine, the amino acid found in apetamin syrup, has led to increased appetite and weight gain in animal studies, but there’s no research on the appetite effects of l-lysine in humans.

Much more research is needed to determine whether apetamin is an effective—and safe—weight gain supplement for humans. 

Apetamin Pills Versus Syrup

Syrup is the more common way to take apetamin, but the drug also comes in pill form. The main difference between the two is that apetamin syrup contains the blend of vitamins and amino acids, while tablets or caplets only contain cyproheptadine hydrochloride.

Is Apetamin Legal? 

It’s currently illegal to sell apetamin in many countries, including the U.S., because apetamin products contain a prescription-only drug called cyproheptadine hydrochloride. Cyproheptadine hydrochloride is an antihistamine used to treat allergy symptoms, such as sneezing, itchy and watery eyes, and runny nose. 

It’s only available with a prescription because of its potential side effects and safety concerns, which, on the severe side, includes liver failure. On top of that, the FDA has not approved and does not regulate apetamin, which means that some (and possibly many) apetamin products don’t accurately disclose what they contain. This presents the risk of toxicity from any undisclosed ingredients. 

Apetamin and other products that contain cyproheptadine hydrochloride are even on the FDA’s list of illegal medical imports to be seized and list of unapproved cough, cold, and allergy products. Because of these reasons, you won’t find apetamin at reputable food, vitamin, or supplement stores in the U.S. 

Potential Benefits of Apetamin

The main reason people take apetamin is to gain weight, and that’s the obvious benefit of the substance. Cyproheptadine hydrochloride has been used as an appetite stimulant in medical settings, particularly for patients with cystic fibrosis, where low appetite is a side effect. It’s also been used to help undernourished children gain weight.

People have used apetamin syrups and pills to help gain muscle and get stronger and prepare for events like powerlifting meets and bodybuilding shows. Many women who are naturally very thin have also used apetamin products to add curves to their figures. 

However, this singular benefit of apetamin—weight gain—does not outweigh the known side effects. 

Side Effects of Apetamin

The side effects of apetamin pills and syrup arise mainly from its active ingredient of cyproheptadine hydrochloride. According to the U.S. Library of Medicine, those side effects are: 

  • Dry mouth
  • Dry sinuses and throat
  • Drowsiness and fatigue
  • Dizziness
  • Nausea
  • Chest congestion
  • Headache
  • Excitement or hyperactivity (particularly in children)
  • Muscle weakness

Rarer, but more severe, side effects of apetamin and cyproheptadine hydrochloride include: 

  • Difficulty urinating (despite drinking water)
  • Distorted vision
  • Excessive nervousness

In the worst-case scenario, the use of apetamin or unprescribed cyproheptadine hydrochloride can lead to liver toxicity and liver failure. Excessive weight gain or obesity is also a risk for those who overuse apetamin.

Is It Safe to Use Apetamin for Weight Gain?

Because of legality issues and lack of regulation from the FDA, you can’t trust apetamin products to contain what they say they contain on the label. Additionally, the side effects of the active ingredient cyproheptadine hydrochloride can be severe without a prescription (and even with a prescription). For those reasons, it’s not safe to use apetamin for weight gain. 

A Word From Verywell

If you’re looking to gain weight, it’s very possible to do so without using illegal supplements. Just like weight loss, intentional weight gain requires an eating and exercising plan tailored to your goals. 

Health professionals that can help you create a plan include doctors, registered dietitians, and personal trainers. Most people can safely and effectively gain weight by eating more calories than they burn, focusing on protein intake, and building muscle by lifting weights

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8 Sources
Verywell Fit uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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