Are Prescription Weight Loss Pills Safe?

Medical Pills

This is one question everyone who wants to embark on the journey of losing weight with prescription drug asks. The simple answer would be “if they are prescribed by a doctor, then it is safe.” As with other medications, there are possible side-effects you should know about. Here’s a look at the popular prescription drugs and their potential side effects.


This is one of the most popular FDA-approved drug used for weight-loss. It is available under different trade names including Alli (available over the counter), Xenical, and XLS Medical.

Orlistat helps you lose weight by blocking your body from absorbing about a third of the fat contained in your diet. The possible side-effects you could encounter when taking orlistat includes:

  • Abdominal cramps
  • Leaking oily stool
  • Unusually high bowel movements
  • Difficulty in controlling bowel movements.

More often than not, the above side effects are mild and temporary. If, however, you eat foods these symptoms may get worse. Contact your doctor if any of these symptoms persist.

Liraglutide (Saxena)

Liraglutide belongs to a class of drugs known as GLP-1 hormone producers and is available only as an injection. Unlike Orlistat that reduces your body’s ability to absorb fat, this drug reduces your appetite. The most common side effects of Liraglutide include:

  • A headache
  • Dizziness
  • Nausea
  • Fatigue
  • Dry mouth, and
  • Constipation.

For people who have diabetes and take this drug, the most common side effects are low blood sugar (hypoglycemia), headache, back pain, cough, and fatigue.


Lorcaserin, also available as Belviq belongs to a group of drugs known as serotonin receptor agonists. This drug works similarly as Liraglutide. When taken, it affects the part of the brain that helps control your appetite, thus, making you feel full after eating an amount of food smaller than your usual quantity. Common side effects include:

  • Nausea
  • Vomiting
  • Diarrhea
  • Constipation
  • Low blood pressure
  • Increased appetite.

There are serious side effects which should not be overlooked. If you notice a raised heart rate, pancreatitis, gallbladder disease, kidney problems, and suicidal thoughts, you should contact your doctor immediately.

Phentermine-Topiramate (Qsymia)

Phentermine and Topiramate are two different drugs taken together to treat weight loss. Although individually they can be used to induce weight loss or treat migraines (Topiramate), when taken together, this medication works by decreasing appetite and by causing feelings of fullness to last longer after eating.

Common side effects of this medication include:

  • Dry mouth
  • Unpleasant taste
  • Diarrhea
  • Constipation
  • Vomiting.

There can also be serious side effects such as raising your blood pressure or causing heart palpitations, restlessness, dizziness, tremor, insomnia, shortness of breath, chest pain, and trouble doing regular activities. Contact your doctor if any of these side effects persist.

Naltrexone-bupropion (Contrave)

Like the previous, this is a combination of drugs. Naltrexone belongs to a class of drugs known as opiate antagonists, and bupropion is an antidepressant. Together, these drugs work on separate parts of the brain to reduce appetite and how much you eat. The most common side effects of this medication include:

  • Nausea
  • Constipation
  • A headache
  • Vomiting
  • Dizziness
  • Insomnia
  • Dry mouth.

More severe side effects are intense seizures (for patients with seizure disorders). In the box of Contrave is warning about the increased risk of suicidal thoughts and behaviors associated with bupropion. The warning also notes that there have been cases of severe neuropsychiatric issues linked to bupropion.

Are Prescription Drugs Safe?

Looking at the possible side effects, one may lose heart on weight loss drugs. The side effects are only ‘possible.’ All the medications stated above are safe for consumption, if they weren’t they possibly wouldn’t have been approved by the FDA for weight loss. The following tips will help you reduce the possibility of having side effects while taking any of these drugs:

  • Always follow your doctor’s instructions.
  • Tell the doctor your medical history before getting a weight loss drug
  • Buy your drugs from a pharmacy or web distributor approved by your doctor.
  • Eat healthily and add a physical activity program to the drug.
  • Try taking your medication at almost the same time each day. If you miss a dose, take it as soon as you remember. However, if it is close to the time for another dose, skip the missed dose.
  • Know the side effects and warnings for taking any medication.
  • If you do not lose any significant weight after 12 weeks, ask your doctor if should stop taking that particular drugs.

Who Should Not Take Weight Loss Drugs?

As with every medicine, some people should avoid taking weight loss drugs. These people are:

  • Pregnant or breastfeeding mothers. Women who plan on getting pregnant are also discouraged from taking most of these drugs.
  • Individuals younger than 18 (Except Alli – a low dosage of Orlistat).
  • Anybody who suffers from a malabsorption syndrome (irregular digestion).
  • People suffering from cholestasis.

Some of these weight loss drugs can also interfere with the absorption of various medicines and vitamins and affect the way that they work. For this reason, it is crucial that you check with your doctor especially if you are on another medication.

Why Take Prescription Drugs to Lose Weight?

If you decide to take any prescription drugs for weight loss, it surely would not be for a few pounds. So what’s in for you if you take weight loss drugs? Research shows that some people taking prescription weight-loss drugs can lose up to 10 percent or more of their starting weight (the result varies with medication and person).

Dropping 10 percent of your weight in a matter of months is excellent, and can help improve your health by lowering blood sugar, blood pressure, triglycerides, relieving joint pain or sleep apnea. There is also the overall feeling of health and wellness.

While weight loss drugs work independently, studies have shown that they work better when taken alongside a lifestyle program. When combined with changes to behavior, including eating and physical activity habits, prescription medications may help some people lose weight.

On average, people who take prescription medications as part of a lifestyle program lose between 3 and 9 percent more of their starting body weight than people in a lifestyle program who do not take medication.

Aaron Gordon is a writer for various blogs.

Leave a Reply

Your email address will not be published. Required fields are marked *