There are many different types of weight-loss drugs and supplements on the market, but there can be many risks to taking these products. You should consult your doctor before starting a new drug. Your doctor may be able to recommend a prescription that can aid weight loss if combined with exercise and a healthy diet, but these do carry risks for people with certain medical conditions. Dietary supplements are another popular option for people looking to lose weight, although they are not regulated by the FDA. Always buy your supplements and medications from reputable sources and make sure that you are using them properly.

Method 1 of 3:
Finding a Prescription Drug

  1. 1
    Visit your doctor. There are many weight-loss drugs that can only be obtain from a doctor. While you are taking these drugs you will be carefully supervised by your doctor. This will ensure that you taking the drug correctly. If any side effects or complications do occur, you and your doctor can handle them quickly and safely. Do not use these drugs without the advice or supervision of a doctor. While visiting your doctor, you should let them know:
    • Your medical history
    • Your family’s medical history
    • Any allergies you have to medications
    • What other medications you are currently taking
    • How else you are handling your weight loss (exercise, diet, etc.)
  2. 2
    Understand your risk factors. Many prescription weight-loss drugs cannot be used by people with certain conditions. While these can vary from drug to drug, you should always inform your doctor of any medical conditions to prevent deadly side effects. Be sure to tell them if you:
    • Have a personal or family history of heart disease
    • Have high blood pressure
    • Suffer from diabetes
    • Are pregnant
    • Smoke cigarettes
  3. 3
    Ask for a prescription weight-loss drug. There are six types of prescription drugs approved by the FDA for weight loss. Each of these has different effects on the body as well as different strengths and risks. You can talk to your doctor about which of these will be most effective for your weight, health, and lifestyle. These drugs are all used in combination with a healthy diet.
    • Phentermine products: These suppress your appetite by blocking the chemicals in your brain that make you feel hungry. You should not take them if you have high blood pressure, glaucoma, an overactive thyroid, or if you have had a stroke. Brands include Adipex-P or Suprenza.[1]
    • Orlistat: This prevents some fat from being absorbed by your body. Do not take orlistat if you have gallbladder problems or if you have chronic malabsorption syndrome. People with kidney or liver problems may also be at risk. Brands include Xenical or Alli.[2] Orlistat also affects the absorption of fat-soluble vitamins, so be sure to discuss this problem with your physician or dietitian. While Alli may be bought over-the-counter without a prescription, you should still consult your doctor first.[3]
    • Lorcaserin Hydrochloride: This drug will suppress your appetite.[4] People with heart, kidney, or liver disease or who have diabetes may be at risk while taking this. Brands include Belviq.[5]
    • Naltrexone HCI with bupropion HCI: This combination of two medications is sold under the name Contrave. Bupropion is typically used to treat depression, and Naltrexone is often used to help people with addiction problems. Both can be used to suppress appetite.[6]
    • Phentermine-topiramate ER: Sold under the name Qsymia, this drug is a combination of an appetite suppressant (phentermine) and an anti-seizure drug (topiramate). People with heart problems, glaucoma, or thyroid issues should not take this drug.[7] It may also be able to help with migraines.[8]
    • Liraglutide: This is an injection that is sometimes used to help treat type II diabetes. The weight loss version is known as Saxenda. It can help suppress appetite. If you have thyroid problems, you should not take this.[9]
  4. 4
    Watch out for side effects. Be aware that no matter what medication you take, there is a chance of side effects. Some of these side effects are mild; others require immediate medical care. Talk to your doctor before you begin so that you know what to look out for. Some common side effects include:[10] [11]
    • Nervousness or anxiety
    • Irritability
    • Headaches
    • Dry mouth
    • Nausea
    • Constipation
    • Abdominal pain
    • Diarrhea
    • Changes in stool color or consistency

Method 2 of 3:
Searching For Dietary Supplements

  1. 1
    Read the ingredient list. The best place to start is the ingredient list. There are hundreds of different types of ingredients used in dietary supplements. Safe ingredients that are commonly found in weight loss supplements include white kidney bean pod, caffeine (in doses under 400 ml), calcium, chitosan, and chromium. Green coffee extract, green tea extract, and raspberry ketone may be safe in small doses.[12] [13]
    • Supplement labels are required to list all active and inactive ingredients, but studies have found that less than 50% of supplement labels listed all the inactive ingredients. They can even have known allergens such as wheat, rice, and soy and not be listed on the label.
    • Even safe supplements can still cause side effects such as headache, gas, or nausea.
    • Some brands will list “energy boosters,” “fat-burning products,” or weight-loss supplements” as ingredients, but these are often used to hide harmful ingredients on the label. Only use products that clearly state which ingredients are in their supplement.
    • When choosing a weight loss supplement, you may encounter labels that call their ingredients “natural,” “standardized,” “certified,” or “verified.” These terms are not regulated by the FDA or any other organization.[14]
  2. 2
    Avoid dangerous ingredients. Some ingredients commonly found in supplements are known to be dangerous. Many of these purport to help you lose weight, but they can also cause heart problems, nervousness, or pain. Avoid using these ingredients.
    • Ephedra, also known as ma huang, has an increased chance of side effects, especially if combined with caffeine. Ephedra can cause stroke, increased blood pressure, and gastrointestinal problems. It is not considered safe to consume, and it is banned in supplements in the US and Canada.[15]
    • Bitter orange is often used as a replacement for ephedra, but it is not necessarily a safer option. It can cause a racing heart rate, anxiety, chest pain, and higher blood pressure.[16] Most evidence based studies found no significant weight loss with bitter orange.[17]
    • While there has not been extensive research on hoodia, some suggest that it might not be safe. It can cause a faster heart rate, dizziness, nausea, or a headache.[18] Some supplements that claim to have hoodia may not actually contain it.[19] It is a rare plant, and takes many years to mature. Therefore it is difficult of obtain true hoodia, and most supplements contain counterfeit or non-active form of hoodia.
    • Yohimbe is a stimulant that may cause heart and respiratory problems.
  3. 3
    Look for quality seals. Some independent organizations offer certification to brands that fulfill their quality guidelines. These organizations, while not affiliated with the FDA, can help you discover if a supplement is authentic. These seals include:
    • approved quality product seal
    • The NSF International dietary supplement certification
    • U.S. Pharmacopeia dietary supplement verification program[20]
  4. 4
    Locate a reputable brand. The U.S. National Institute of Health and the National Library of Medicine operate a database of brands and manufacturers of dietary supplements. These can help you compare ingredients, identify brands that contain particular ingredients, and find which brands contain harmful ingredients.
    • This database also contains the contact information of each manufacturer. If you have questions or concerns about the supplement, it is recommended that you contact the manufacturer.[21]

Method 3 of 3:
Buying and Using Safe Supplements

  1. 1
    Fulfill your prescription at a pharmacy. Some online vendors offer seemingly cheap versions of prescription weight-loss drugs. Do not buy these. They are often fake products that contain dangerous ingredients. Some may be expired, the wrong dosage, or damaged. With prescription weight-loss drugs, you should always get them from a pharmacy to make sure that they contain the proper, safe ingredients and dosage.
  2. 2
    Buy your over-the-counter products from a reputable source. Weight loss products are known to sometimes be counterfeited or poorly manufactured. These products may be contaminated with dangerous ingredients or have hidden additives that can affect your health. Exercise caution when buying supplements.[22] It may be better to buy your supplements in a physical store where you can inspect the packaging, the quality, and the brand. You will also be able to compare several brands.
    • You can ask a pharmacist for reputable supplement brands. They can also warn you of any suspicious ingredients hiding in the ingredient list.
    • ConsumerLab has a list of approved online vendors. These vendors have been verified as providing safe, uncontaminated supplements.[23]
    • Some types of Alli bought online have been found to contain sibutramine (Meridia), which can cause severe or dangerous side effects.[24]
  3. 3
    Avoid weight-loss drugs if you are pregnant. Many supplements and drugs have not been tested on pregnant women. It is unknown whether they could have harmful effects on the fetus.[25] Work with your doctor instead on a healthy diet that will benefit both you and your baby.
    • Qsymia is known to increase the risk of birth defects.[26]
  4. 4
    Stop taking supplements before surgery. If you have a planned surgery, you should stop taking supplements a few weeks beforehand. Some supplements can interfere with medications, anesthesia, or blood clotting, thus increasing your risk of complications both during and after the surgery. Inform your doctors of any supplements you are taking, and follow their directions if they advise you to stop.[27]

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      • Always inform your doctor when starting a new supplement or drug.
      • Weight-loss drugs are complementary medicine. This means that they work most effectively when combined with exercise, a healthy diet, and other treatments. Weight-loss drugs are rarely effective on their own.
      • If a claim sounds too good to be true, it probably is.



      • Supplements do not offer impressive results for weight loss, and many cause harmful side effects. Supplements are poorly monitored for purity and consistency of ingredients, and are in the “buyer beware” category of goods.
      • Never share your prescription weight loss medication with anyone else.
      • Children should not take weight loss medication. Store your prescription drug in a place where they cannot reach it.
      • If you are experiencing side effects, stop the medication immediately, and contact a doctor.

      About This Article

      Patricia Somers, RD, PhD
      Co-authored by:
      Registered Dietitian
      This article was co-authored by Patricia Somers, RD, PhD. Patricia Somers is a Registered Dietitian and an Associate Professor of the Department of Educational Leadership and Policy at the University of Texas at Austin. She received her RD from the Academy of Nutrition and Dietetics in 1979 and her PhD in Educational Administration (Higher Education Specialization) from the University of New Orleans. She received an Emerging Scholar Award from the American Association of University Women and the Faculty Excellence Award in Research from the University of Arkansas, Little Rock. This article has been viewed 138,664 times.
      1 votes - 100%
      Co-authors: 6
      Updated: March 29, 2019
      Views: 138,664
      Thanks to all authors for creating a page that has been read 138,664 times.

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