Prescription drugs may cause unnecessary weight gain

Medications taken by millions of Americans for mood disorders, high blood pressure, diabetes, and other chronic diseases have the unhealthy side effect of weight gain.

The drugs are not only a cause of weight gain, says Ryan Lu, director of pharmacy for the Harris County Hospital District in Houston, but they also have the potential to cause a number of other side effects, including weight gain.

In the late 1990s, Dr. Lawrence Cheskin conducted an early study on prescription drugs and obesity.

He said, “Certain medications produce noticeable changes early on, making patients hunger voraciously, while others are subtle. The changes are subtle, says Cheskin, who is now director of the Johns Hopkins Center for Weight Management in Baltimore.

To raise awareness, Lew and his group of pharmacists have developed a list of “weight gain-promoting” and “weight-neutral or weight-loss” drugs.

Antidepressants that promote weight gain include Paxil (paroxetine), Zoloft (sertraline), amitriptyline (Elavil), and Remeron (mirtazapine).

Wellbutrin (bupropion) and Prozac (fluoxetine) are considered weight-neutral or weight-loss drugs.

In general, older antidepressants are more likely to cause weight gain than the newer SSRIs (selective serotonin reuptake inhibitors),” Cheskin said.

Mood disorder medications that may cause weight gain include the antipsychotics Clozaril (clozapine), Zyprexa (olanzapine), Risperdal (risperidone), and Seroquel (quetiapine). Lithium, valproic acid (Depakote), and carbamazepine (Tegretol) may also increase weight.

Hormonal medications such as antipsychotics and steroids are the biggest cause of weight gain, Cheskin says. These drugs affect the brain, and appetite control is largely a function of brain function. Appetite control is largely a function of brain function.

Both experts agreed that poor adherence to prescribed medications is common, regardless of whether or not it affects a patient’s weight.

In the case of antipsychotic medications, once patients feel better, they may stop taking them. If a drug such as Zyprexa, used for schizophrenia or bipolar disorder, causes weight gain of 20 pounds or more, this is also a barrier to treatment adherence.

Blood pressure medications that can cause weight gain include Lopressor (metoprolol), Tenormin (atenolol), Inderal (propranolol), Norvasc (amlodipine), and Clonidine (Catapres).

According to Cheskin, improving one’s diet can offset the effects of these drugs. ‘I recommend increasing fiber and fluids and decreasing calorie density,’ he says. Instead of saving calories for dinner, spread the calories over several meals, five or six times a day,” he said.

Corticosteroids like prednisone and methylprednisolone are important in treating conditions like rheumatoid arthritis, asthma, and certain types of cancer, but they are notorious for causing weight gain.

Steroids cause fat accumulation. Excess weight often accumulates in the trunk, which retains salt and fluids, he says.

Instead of giving up steroids, talk to your doctor and see if there are alternative therapies. With steroids, you may be able to take them every other day or in smaller doses. But if steroids are necessary, there is no alternative to steroids,” he said.

Diabetes medications, including oral drugs like Actos (pioglitazone) and Amaryl (glimepiride), promote weight gain, as does insulin.

In the case of insulin, much is chicken and egg. ‘Obese people get diabetes, and people with diabetes have mechanisms that make them less responsive to dietary changes.

Weight-loss or weight-neutral alternatives to oral diabetes medications exist: Bayetta (exenatide), Januvia (sitagliptin), Simlin (pramlintide), Precose (acarbose), and metformin (biguanides).

Epilepsy medications prevent seizures. Some, like carbamazepine and neurontin (gabapentin), cause weight gain. Possible alternatives include Lamictal (lamotrigine), Topamax (topiramate), and Zonegran (zonisamide).

According to Roux, women on birth control pills may also “gain a lot of weight.”

Switching to weight-neutral drugs does not work for everyone, Lew cautioned.

These drugs have different mechanisms of action and may not control a person’s unique condition. First and foremost, it is the disease state that is causing the greatest disruption to a person’s lifestyle. That should be our first priority.”

People who are struggling with weight gain should talk to their health care provider, Lew says.

“I encourage them to talk to their pharmacist first so they don’t stop the medication on their own before their next visit.” For both patients and health care providers, there should be no shame in delving into a person’s comfort level with medication therapy.”

And, Cheskin added, “With all the focus on environmental factors as a cause of obesity, people may not realize that what we are prescribing may not help you, and may even steer someone in the wrong direction.”