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Contrave Side Effects: Benefits and Complications of Weight Loss Pill

Contrave is a hot new weight loss pill. How well does it work and what are the side effects? Is this the magic answer to obesity or an overhyped drugs?
Contrave Side Effects: Benefits and Complications of Weight ...
Obese obesity overweight weight loss

Q. I am a 56-year-old female who had my thyroid removed in 2006. Fortunately, there were no signs of cancer.

Of course, without a thyroid gland I have been on thyroid medication ever since. I am having trouble keeping my hormone levels where they would like to see them so the doctors are always changing my dose and my meds.

Because of all this I have a tendency to gain weight. I am having trouble losing it, so my doctors have suggested I try Contrave. I am wondering what you think of this medication.

A. We have some serious concerns about Contrave. It is a formulation containing two different drugs,Bupropion and Naltrexone.

Bupropion (Wellbutrin) is an antidepressant medication that has also been used to help people stop smoking (under the brand Zyban). Naltrexone (Revia, Depade) is an opioid antagonist (blocker). In other words, Naltrexone reverses the effects of narcotics like heroin, morphine or other opioid medications like oxycodone (Oxycontin, Percocet, Roxicodone, etc) or hydrocodone (Vicodin, Lorcet, etc). Naltrexone has been approved to help people overcome narcotic addiction as well as alcohol dependence.

Why Would Bupropion and Naltrexone Help People Lose Weight?

There was a hint that, individually, bupropion or naltrexone might help people lose weight. One of the side effects of bupropion is loss of appetite. The drug affects neurochemicals in the brain to alleviate depression, so it is not entirely surprising that it might impact a range of behaviors, including eating.

Naltrexone blocks natural opioid receptors in the brain, which is why it has been used to treat alcoholism and other compulsive behaviors (gambling, hair pulling, kleptomania, etc.). It might counteract compulsive eating.

How Good Is Contrave for Losing Weight?

The first thing you must know is that the clinical trials involved people who were very seriously overweight. Subjects had to have a BMI (body mass index) of 30 or greater. For example, someone who is 5 feet 10 inches tall and weighs 212 pounds would have a BMI of 30.42. People with a BMI of 27 or greater would be considered eligible for the drug only if they had some other condition like high blood pressure or type 2 diabetes. Bottom line, this is not a drug approved for modest weight loss of 10 to 15 pounds.

In a company-sponsored trial, people lost about 4 to 5 percent of their weight after a year compared to placebo. Something, but not a dramatic difference. In studies involving over 4,000 people, those on Contrave lost roughly 8 pounds more than those on placebo if they stayed on the drug for more than six months. These people were also engaged in a weight-management program in addition to taking the pills.

Are you excited yet? We’re not dazzled either. Here’s a fascinating statistic. A lot of people taking Contrave pulled out of the clinical trials. According to the official prescribing data that number was 46%. That is surprisingly high. At least half pulled out because of side effects associated with Contrave.

Side Effects of Contrave

So what are the problems with this weight-loss medication? First and foremost are the digestive tract complications! Roughly one third of the clinical trial subjects taking Contrave experienced GI complaints while taking this pill.

  • Digestive distress (nausea, vomiting, constipation, diarrhea, abdominal pain, belching, gastroenteritis, taste disturbances, etc.)
  • Headache
  • Dizziness, vertigo
  • Insomnia, sleep disorders
  • Dry mouth, thirst, dehydration
  • Anxiety, irritability, jittery, tremor, palpitations
  • Confusion, cognitive impairment, memory problems, amnesia, abnormal dreams
  • Ringing in the ears
  • Sweating
  • Increased blood pressure

Special Warnings Regarding Contrave

The FDA has required the manufacturer of Contrave to advise potential patients about a risk of suicidal thoughts and advises families and caregivers to monitor people taking the drug for suicidal thoughts or behaviors. There is also reference to “neuropsychiatric reactions,” so people should be watched for any unusual thinking patterns or behaviors.

Bottom Line from The People’s Pharmacy:

Contrave should not be considered a routine weight loss pill. It is approved for those who are really obese or overweight with a medical condition like hypertension or type 2 diabetes. The complication, though, is that the Contrave may actually increase blood pressure. And people with type 2 diabetes may be more susceptible to side effects like nausea and vomiting.

The side effects of Contrave are not trivial. Although a high incidence of nausea is likely to discourage people from eating, we do not think this is a desirable way to lose weight.

Our conclusion is that weight loss on Contrave is modest at best and side effects make this drug problematic. A program of regular exercise and carbohydrate restriction with support from friends, family and even a supervised group may produce lasting benefits without the risks of medications.

PS…you mention you are having problems getting your thyroid dose adjusted and that is in part contributing to your weight gain. You may find our Guide to Thyroid Hormones helpful in better understanding condition so that you might not need a diet pill at all.

If you have taken Contrave we would love to learn how you fared. Did you lose a lot of weight? Did you experience any side effects? Please share your story below in the comment section. And please vote on this article at the top of the page.

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About the Author
Joe Graedon is a pharmacologist who has dedicated his career to making drug information understandable to consumers. His best-selling book, The People’s Pharmacy, was published in 1976 and led to a syndicated newspaper column, syndicated public radio show and web site. In 2006, Long Island University awarded him an honorary doctorate as “one of the country's leading drug experts for the consumer.” .
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