When you start a weight loss medication, it’s common to have side effects in the beginning. Side effects happen because your body is adjusting to the medication. Usually, these go away within the first few weeks. There are some things you can do to help manage these side effects.
Weight loss medications usually target how your digestive system works. Any changes that happen to your digestive system—like feeling less hungry, digesting food more slowly, or even absorbing less fat—may lead to a side effect.
Here are some tips for managing these side effects, if you have them.
Nausea
With some weight loss medications, food moves out of your stomach more slowly. This means food stays in your stomach longer and can lead to nausea.
With other weight loss medications, you may have less appetite. You may be in the habit of eating large meals, because that is what you are used to. If you eat too much without having an appetite for food, this could lead to nausea too.
Here are some tips to help with nausea while on a weight loss medication:
- Eat smaller meals. Since food may stay in your stomach longer, or you may have a lower appetite, try having less food at each serving. If you’re worried about being hungry, you can eat small meals and snacks more frequently throughout the day.
- Cut back on high-fat meals. Greasy, buttery, or oily meals take a long time to digest. Since food may already be staying in your stomach longer, having less fatty foods may help.
- Eat fiber in moderation. High-fiber foods (like beans, whole grains, and vegetables) take longer to digest. While fiber is good for your health, having too much fiber at once can lead to nausea if you have a slower digestive system.
Vomiting
If you have nausea, there’s a chance it could lead to vomiting. Vomiting could make you dehydrated.
Here are some tips to help with vomiting:
- Drink water, low-sugar electrolyte drinks, or chicken broth. Taking small sips frequently can help you stay hydrated without feeling like you need to vomit again.
- Choose bland foods. Vomiting can be triggered by spices and smells. Try to eat foods that are bland like toast, rice, peanut butter, chicken, or crackers.
- Most importantly, if your vomiting persists for more than a day, contact your health care provider. Vomiting too much for too long can lead to serious dehydration. Your health care provider may need to change your medication.
Diarrhea
If you have diarrhea while taking a weight loss medication, it’s also important to stay hydrated. You can lose electrolytes with loose stools.
Here are some tips to help with diarrhea while on a weight loss medication:
- Drink water, sip on chicken broth, or try low- or no-sugar electrolyte drinks to replenish electrolytes.
- To bulk up your stool, try to eat foods with more soluble fiber, the type of fiber that absorbs water. Foods like oats, bananas, toast, rice, and apples may help.
- If your diarrhea persists for longer than a few days, contact your health care provider. They may need to change your medication.
Constipation
In some cases, you may have constipation instead of diarrhea. Because your digestive system may be moving more slowly, you may start to feel “backed up.”
Here are some tips to relieve constipation:
- Drink more water. Staying hydrated will help to loosen your stools.
- Take a walk. Gentle movement like walking, yoga, or stretching may get your bowels moving.
- Try to relax. Your digestive system works best when you are feeling relaxed. Try some deep breathing or meditation to help you calm down.
- Gradually eat more high-fiber foods. Fiber is important for staying regular. But having too much all at once can actually clog you up. Slowly incorporate more foods with fiber. Make sure to increase the amount of water you drink as you do this. Water and fiber go hand-in-hand!
Some side effects are common when starting a weight loss medication. They usually go away within the first couple of weeks. You may also have side effects if your doctor or healthcare provider increases the dose of your weight loss medication. If you experience side effects, try a few of these tips to see if you find relief.
However, if side effects are making it hard to get through your day, talk with your doctor or healthcare provider. They may want to change your medication. You can always ask to go to a lower dose of the medication. Or, you can ask to stay on a lower dose for longer before starting a higher dose. These are important conversations to have with your doctor or healthcare provider if you are having side effects from weight loss medications.
Note: Anyone prescribed these medications should read the medication guide for the full list of side effects and use instructions. In addition, these medications should only be prescribed under the care of a physician.
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