What Is Apetamin?

Illegal Supplement Used to Promote Weight Gain

Apetamin for weight gain

Verywell / Alexandra Shytsman

Some people struggle to gain weight when their doctor or nutritionist recommends it or when trying to build muscle mass. This happens for various reasons. Some people are genetically very thin; some 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 inadequate food intake, and some people want to put on muscle but find it a struggle. 

A recent trend in the weight gain industry had people turning to an illicit supplement — apetamin pills. 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, why it’s illegal, and what 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 that 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 several 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. 

Why People Take 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 malnourished children gain weight.

People have used apetamin syrups and pills to help gain muscle, get stronger, and prepare for events like powerlifting meets and bodybuilding shows. Many naturally very thin women 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. 

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 exist. 

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

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

In animal studies, L-lysine, the amino acid found in apetamin syrup, has led to increased appetite and weight gain. Still, 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 a 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, include 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. 

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

Severe Side Effects of Apetamin

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

In the worst-case scenario, using 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 have 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 unsafe to use apetamin for weight gain. 

A Word From Verywell

If you’re looking to gain weight, it’s possible to do so without using illegal supplements. Just like weight loss, intentional weight gain requires 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

7 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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By Amanda Capritto, ACE-CPT, INHC
Amanda Capritto, ACE-CPT, INHC, is an advocate for simple health and wellness. She writes about nutrition, exercise and overall well-being.