Antidepressants are used for weight loss, but should be the last option

Although the prescription of antidepressants to treat obesity is considered adequate by specialists in some cases, patients report insecurity and lack of information regarding the use of the drugs. Fluoxetine, sertraline and bupropion hydrochloride are the most recommended in the office.

According to Fábio Trujilho, director of the obesity department at SBEM (Brazilian Society of Endocrinology and Metabology) and vice-president of Abeso (Brazilian Association for the Study of Obesity and Metabolic Syndrome), the institutions he represents consider it correct to prescribe antidepressants for the obesity treatment provided that the alternative is recommended for patients who have not responded satisfactorily to specific drugs for the purpose, such as sibutramine and orlistat.

The use of drugs to treat diseases other than those specified in the package insert and approved by Anvisa (Brazilian Health Surveillance Agency) is known as off-label. Although there is no manufacturer’s recommendation, the drugs most used for purposes other than those indicated are supported by scientific studies that prove their effectiveness, says Trujilho.

In a note, Anvisa states that “it does not regulate off-label use. However, this use must be based on scientific evidence and supported by the responsibility of the prescribing physician from the assessment of the clinical condition of each patient”.

According to Durval Ribas, president of Abran (Brazilian Association of Nutrology), some antidepressants work for weight loss because they act on the central nervous system in the same way as most anti-obesity drugs.

“It was noticed that some antidepressants had an effect on the central nervous system related to neurotransmitters that were directly linked to the hunger and satiety mechanism”, says Ribas.

Although professionals point out that prescription is recommended in some cases, patients report insecurity and lack of information.

Maria (not her real name, on request) says that despite losing weight in the first few months she took fluoxetine, she gained weight again and saw no long-term benefits. In addition to the accordion effect, she reports nausea and irritability as disadvantages of treatment conducted by an endocrinologist.

According to her, the insecurity when taking the antidepressant was also a problem, since the doctor did not properly explain the reason for the prescription.

“I think that most of the time the medication is given without giving the person other alternatives”, he says. After the frustration with the treatment, she decided to intensify her diet and exercise.

A similar case is that of Ana Paula Siqueira, 54, a public relations professional who took antidepressants to treat overweight at two times in her life. Although always with medical indication, Siqueira reports having felt bad with the treatment. She believes the prescription was not adequate.

Encouraged by her psychologist, Siqueira stopped using sertraline after only 10 days of use. “I felt guilty,” she says.

After the experience, she lost 10 kg with diet and exercise. Today, she focuses on this type of treatment as she considers a more natural strategy, in addition to using an injection to treat prediabetes.

For José Carlos Appolinário, psychiatrist and coordinator of the Eating Disorders Commission of the ABP (Brazilian Association of Psychiatry), the use of antidepressants to treat obesity should only occur after other alternatives have been exhausted. According to him, there are not enough studies to guarantee the effectiveness of the treatment in the long term.

The psychiatrist explains that, although the isolated use of the drugs does not have this proof, Anvisa released the association of bupropion with naltrexone, a drug used to combat addiction to opiates and alcohol, for anti-obesity treatment.

According to Appolinário, the patient who receives the prescription of antidepressants to lose weight should, whenever in doubt, seek the follow-up of a psychiatrist.

Endocrinologist Fábio Trujilho reinforces that not all treatment needs to be medicated, but that it is necessary to demystify the use of medication for those who need it.

“Well prescribed medication, for the right person in the right dose, will help. But we also see indiscriminate use and prescriptions that are not adequate”, he says.

According to Trujilho, the use of medication is indicated for patients who have a BMI (body mass index) greater than 30 and who have not lost weight only through lifestyle changes. People with a BMI greater than 27 and with other obesity-related comorbidities, such as osteoarthritis or fatty liver, also fit the indication.

The doctor says that the way the professional approaches the topic with the patient is also important. According to him, the correct thing is to explain the alternatives to the patients, who must have an active posture during the consultation, and not impose forms of treatment.

Finally, Trujilho declares that the patient should never self-medicate or undergo treatment without the follow-up of a specialist. The risks of using drugs without medical supervision are several, such as worsening hypertension, cardiovascular complications, tachycardia, emotional imbalance and death, he says.