Prescriber Education Needed for Drug-Induced Weight Gain

In addition to diet, exercise, and behavior modification, another significant method to prevent weight gain in patients with obesity is to avoid or minimize treatment with medications known to cause patients to gain weight.

Side effects can cause a host of adverse events, including weight gain. For patients with obesity, taking drugs that increase their weight further exacerbates health burden.

A new study published by Gastroenterology suggests that physicians should review side effects and interactions of medications prescribed to patients with obesity. Providers should also become familiar with alternative drugs that limit weight gain, or even lead to weight loss.

"Physicians know that some medications can increase weight, but they don't always know what alternatives are out there," said lead author Leon Igel, MD. "We want physicians who treat patients with obesity to feel more comfortable prescribing these alternatives. Our paper looks at how to practically manage patients with obesity by prescribing the optimal medications for them."

Steroids and contraceptives are commonly used medications that restrict the ability to lose weight. Other medications, such as insulin, metaprolol, and paroxetine, which treat diabetes, hypertension, and depression, respectively, also increase weight, according to the study.

Unfortunately, weight gain is not always a concern when a physician prescribes a certain drug.

"Each practitioner has a goal in mind," Dr Igel said. "A cardiologist wants to lower blood pressure. A psychiatrist wants to make sure that mood is well regulated. They're not necessarily focusing on which medications will affect weight, but rather what will achieve their treatment goal."

The study authors suggest that it is critical for prescribers to become aware of the full side effect profile of the drugs they prescribe, and how they might interact with other medications. Physicians should also recognize when they can substitute a drug for one that may not cause weight gain.

While some patients require insulin treatment, adding other drugs that promote weight loss may neutralize insulin-induced weight loss, according to the study.

Since obesity affects one-third of Americans, medication-related weight gain should be a concern for providers. There has been limited uptake of drugs approved to reduce weight, likely due to the fact that insurers may not cover it, and physicians are unsure which patients are candidates for the treatment, according to the study.

Despite a potential lack of knowledge among physicians, they should become more aware of the optimal candidates for certain weight loss drugs, and when others should be avoided. For example, the study authors said that patients with uncontrolled hypertension, coronary disease, hyperthyroidism, or glaucoma should avoid phentermine, which is a stimulant that suppresses appetite. For these patients, the drug would cause harmful side effects.

"We wanted to provide extra guidance, so that practitioners are using the right types of medications for the right types of patients," Dr Igel concluded.