Are Weight Gain Pills Safe?

Prescription drugs are regulated, while OTC supplements are unregulated

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While many people are working to lose weight, others struggle to gain weight. If you'd like to increase your strength, build a more muscular physique, or return to a healthy weight after losing too much, there are healthy and unhealthy ways to go about it. Weight gain pills and supplements may be effective in some cases but are not risk-free. Focus on a healthful diet to promote weight gain and proper training to support your goals.

Before you take any supplement—even one you can get over-the-counter (OTC)—you need to know what's in it, how it is intended to be used, and the risks associated with it.

What Are Weight Gain Pills?

Weight gain pills include over-the-counter supplements and medications prescribed by a physician. Although supplements claim to support safe and natural weight gain, over-the-counter products are largely unregulated and often not backed by scientific evidence.

If you're curious about weight gain pills, talk to your healthcare provider about the products you are considering. Here is what you need to know about weight gain supplements and why it's helpful to involve your provider in the decision-making process.

If you are not certain whether you should try to gain weight, speak with a healthcare provider to determine an optimal weight range for your health and lifestyle. You also should seek their advice about weight gain pills. These supplements are not right for everyone.

Prescription Medication for Weight Gain

Prescription weight gain pills include anabolic steroids. Your provider might consider steroid medication if you have experienced significant weight loss and are underweight due to an illness, such as cancer or muscular dystrophy.

Athletes and bodybuilders may use prescribed drugs illegally to build muscle and enhance athletic performance. Inappropriate use of anabolic steroids comes with multiple health risks—some of which are serious. It's vital that you only take these drugs under the care of a physician.

Potential Side Effects

Anabolic steroids have many possible side effects. Some of the most common reported side effects (organized in order of their impact on organ systems) include:

  • Delusions
  • Extreme irritability
  • Impaired judgment
  • Enlarged heart
  • Kidney problems or failure
  • Liver damage
  • Increased facial hair
  • Mood disorders
  • Mood swings
  • Breast development (in males)
  • Shrinking testicles
  • Stopped menstrual cycle
  • Enlarged clitoris
  • Prostate cancer
  • Stunted growth (in children and teens)

Legal Use

In some cases, the benefits of prescription weight gain pills outweigh the risks. Your doctor can determine whether or not you should be taking them. Here are three common weight gain pills that a healthcare provider might prescribe:

  • Methyltestosterone: This is an anabolic steroid primarily used to boost testosterone levels in males with androgen deficiency (low levels of male sex hormones). Athletes might use this drug and other anabolic steroids to put on weight, and increase muscle mass and strength. However, this use is illegal.
  • Oxandrolone: This is an anabolic steroid that is also known as Anavar. It’s primarily used to promote weight gain in patients who have experienced weight loss after extensive surgery, chronic infection, or severe trauma. It can also be used as hormone replacement therapy for low testosterone levels.
  • Oxymetholone: This synthetic hormone is also considered an anabolic steroid. It is primarily used to promote weight gain in patients who have lost weight due to a debilitating disease. People might also have an oxymetholone prescription to gain weight after having extensive surgery, chronic infection, or severe trauma.

Over-The-Counter Weight Gainers

Several weight gain pills and powders are available over the counter at supermarkets, big box stores, and pharmacies. Like many other supplements, these products are typically packaged and marketed with overstated promises and guarantees.

Weight gainer products may claim to produce a more robust appetite, reduce metabolism, and cause weight gain in specific areas of the body. Just as there is no such thing as spot reduction for weight loss, there is no way to direct weight gain to a particular area of the body through supplements alone.

A lack of regulation by the Food and Drug Administration (FDA) means that supplement producers can essentially say whatever they want to sell their products.

If a weight gain pill or supplement makes claims that seem too good to be true, they probably are.

Additives and Side Effects

Many OTC weight gain pills appear to be nothing but glorified, expensive multi-vitamins. It's important to watch out for blended products that contain potentially harmful ingredients.

Caffeine and guarana may be added to supplements as a way to give workouts a boost. While these additives are generally safe in moderate amounts, there is no way to know how much you're getting in an unregulated OTC product. It's possible to become dependent on stimulants with regular use and feel fatigued without them. If you have an underlying heart condition or difficulty sleeping, stimulants can harm your health.

Echinacea is also included in some weight gain products. Although research is not definitive, echinacea is thought to have anti-inflammatory effects that may benefit the immune system. There is no good evidence in humans that echinacea helps with weight gain.

Another common weight gain supplement is creatine. Creatine causes muscles to hold extra water. Anyone with Parkinson's disease, bipolar disorder, or kidney disease should avoid creatine supplements.

Adverse Effects and Risks

  • Adverse effects of weight gain pills can include nausea, upset stomach, and diarrhea.
  • Individuals who are sensitive to herbs and grasses might have an allergic reaction to additives in weight gain pills (including asthma symptoms, skin rashes, or anaphylaxis).
  • People with heart conditions might be at an increased risk for an irregular heartbeat.

Natural Ways to Gain Weight

According to the Academy of Nutrition and Dietetics, the evidence for the effectiveness of weight gain pills is limited. If you need to gain weight, there are healthier, safer, evidence-backed ways, such as adding more calorie-dense foods to your diet.

Everyone is different, and what works for one person might not work for someone else. Working with a registered dietitian can give you personalized recommendations for what your body needs to gain weight in a safe, healthy way.

Healthy weight gain takes time. Instead of looking for a quick fix, try taking a closer look at what you are eating and the type of exercise you engage in. You might not get enough calories or protein in your diet to support weight gain. 

A Word From Verywell

While the claims and promises of over-the-counter weight gain pills might look promising, do not take these supplements without talking to a healthcare provider. They can have serious side effects and risks, and there are other options for gaining weight safely.

Speak with a healthcare provider and a registered dietitian if you have difficulty gaining weight. Depending on your circumstances, specific recommendations will be made for you. If your provider thinks a medication or supplement could be helpful, they can work with you on finding the right fit.

9 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 Darla Leal
Darla Leal is a Master Fitness Trainer, freelance writer, and the creator of Stay Healthy Fitness, where she embraces a "fit-over-55" lifestyle.