Managing common side effects from weight-loss drugs

Introducing our new program: Mayo Clinic Diet for Weight-Loss Medications.

As with most medications, weight-loss medications may come with side effects. Many of the effects are mild and temporary. It’s common for these concerns to improve with time as your body adjusts to changes in your diet, how much food you eat, and your calorie level. It may take from a few days to a few weeks to begin to see a reduction in symptoms.

You can avoid, or minimize, many common side effects by working closely with your prescribing provider to ensure you take the correct dose of medication, are eating a well-balanced diet and drinking enough water.

Here are the most common side effects and helpful tips to help manage them.

Note: If your symptoms are severe, last for several days, or you are unable to drink fluids or eat food, it is vital that you contact your doctor immediately.

Nausea or reduced appetite

Nausea is one of the most common side effects. The good news is, the feelings of nausea are often short lived and go away once your body has adjusted to the medication. If you’re experiencing severe nausea or vomiting, reach out to your doctor.

Helpful tips:

• Eat smaller, more frequent meals, avoid skipping meals.
• Try cool and bland foods like crackers, toast, or pretzels.
• Avoid high-fat, rich meals like fried foods or foods with strong odors.
• Eat more slowly.
• Drink water or ginger herbal tea regularly throughout the day between meals.
• Don't lie down after a meal.
• Get some fresh air.

Constipation, diarrhea, or stomach pain

Some weight-loss drugs work by slowing down digestion. This can affect the digestive system and may cause side effects such as constipation and stomach pain. Also, when you change your diet, especially if you increase the amount of fiber in your meals, it’s not uncommon to experience mild bowel changes, including diarrhea and stomach pain.

Helpful tips:

• Drink plenty of fluids, mostly water.
• Follow a well-balanced meal plan and eat regular, small meals.
• When adding fiber to your diet, do so gradually over a few weeks.
• Exercise daily. Exercise helps reduce constipation.

Heartburn or gassiness

Slowed digestion also can cause reflux of stomach acids into your esophagus and increased gas in your intestines. In addition, you may find yourself passing more gas than normal as your gut adapts to new foods and changes to your fiber intake. Constipation can produce intestinal gas as well. The longer food remains in your colon, the more time it has to ferment.

Helpful tips:

• Avoid foods and beverages that may worsen reflux, including acidic foods and spicy foods, fried foods, beverages and foods containing caffeine, chocolate, alcohol, peppermint, or spearmint.
• Avoid high-fat meals and foods like fried foods.
• Eat smaller meals.
• Eat more slowly.
• Don't lie down after a meal.

Headaches or fatigue

Headaches and fatigue can be a sign of dehydration, or they can result from a large reduction in calories, sugar, simple carbohydrates, or caffeine that causes withdrawal-like symptoms. These symptoms generally improve as your body adjusts to its new dietary regimen.

Helpful tips:

• Drink plenty of fluids, mainly water.
• Follow a well-balanced meal plan and eat regular, small meals.
• Exercise daily.
• Get enough sleep each night, generally seven to eight hours.

Changes in taste

It’s not clearly understood why, but some people experience changes in their sense of taste, such as having a metallic taste in their mouth, when taking a weight-loss medication. This can affect your appetite.

Helpful tips:

• Regularly sip on water throughout the day.
• Suck on ice cubes.
• Eat frozen fruit like grapes, melon or peach slices.

More serious, less common side effects

On rare occasions, some weight-loss medications can cause symptoms including dizziness, light-headedness, shakiness, or sweating. These symptoms may be due to the medication, they may be a symptom of dehydration, or they may result from a blood glucose level that’s too low (hypoglycemia). If you experience severe dizziness, shakiness, or sweating, reach out immediately to your health care team.

If you have diabetes and your blood glucose level falls below 70 milligrams per deciliter (mg/dL), eat or drink something that provides 15 grams of carbohydrates, such as 4 ounces of fruit juice or regular (not diet) soda, or sugary candy, such as jelly beans or candy corn. Once your blood sugar is back in the standard range, have a healthy snack or meal to prevent another drop in blood glucose.

Although uncommon, weight-loss medications also can cause other serious side effects, including an inflamed pancreas (pancreatitis), gallstones, kidney problems, or allergic reactions. Contact your healthcare team immediately if you experience severe stomach pain, severe vomiting, fever, clay-colored stools, or signs of an allergic reaction. Indications of an allergic reaction may include swelling of your face, lips, tongue, or throat; problems breathing or swallowing; a severe rash or itching; fainting or feeling dizzy; or a very rapid heartbeat.

How the Mayo Clinic Diet can support you

If you are interested in exploring weight-loss medications, it is essential to work closely with an experienced healthcare provider to determine if it is the right treatment option for you. A comprehensive weight-loss program that includes diet, exercise, and lifestyle changes is also recommended in conjunction with weight-loss medications to achieve the best results. 

Using GLP-1s? The Mayo Clinic Diet now supports your journey with a special Companion program for weight-loss medication.