How to Avoid GLP-1 Side Effects if You Have Type 2 Diabetes

GLP-1 receptor agonists, such as semaglutide, and dual agonists, like tirzepatide, have become powerful tools for managing type 2 diabetes. But, like any medication, they can come with side effects.

From nausea and constipation to fatigue and temporary hair loss, reactions can range from mildly inconvenient to completely intolerable. The good news? Most people can manage, minimize, or even sidestep side effects completely with the right preparation and a few tweaks to their treatment.

Common Side Effects of GLP-1s

“The majority of people will experience some degree of gastrointestinal issues with a GLP-1, especially as we start the medication and increase the dose,” says Shiara Ortiz-Pujols, MD, MPH, a weight management physician at Northwell Health Physician Partners Surgery in Staten Island, New York.

Many of the side effects listed below can happen to anyone, but some people — such as those with underlying gastric motility disorders or gastroparesis — are more likely to experience them than others, says Kristin Criner, MD, an endocrinologist and an associate professor of clinical medicine at the Lewis Katz School of Medicine at Temple University in Philadelphia.

If you’re starting a GLP-1, here’s how to recognize (and hopefully minimize) the most common side effects.

Nausea and Vomiting

Nausea typically occurs within 24 to 48 hours, says Dr. Ortiz-Pujols. Usually it’s mild, but severe nausea and vomiting can lead to dehydration or — rarely — acute kidney injury or gastrointestinal obstruction, says Dr. Criner.

You may also notice that certain foods are more likely to trigger nausea than others. Some common offenders include greasy, high-fat, processed, and spicy foods, as well as alcohol and carbonated beverages, says Ortiz-Pujols. If that’s the case, you may want to limit them in your diet overall. A nutritionist can help you determine which foods to avoid.

Constipation and Diarrhea

Both slowness in the gut and an urgent need to go are common side effects, says Ortiz-Pujols. “Initially, you might feel that your bowel movements are slowing down in frequency. And as we go up in dose, that often becomes more pronounced,” she says.

Sometimes, constipation can also shift to urgent diarrhea, says Ortiz-Pujols. If you get diarrhea, try limiting your intake of greasy and more processed foods, she says. You should also make sure you’re drinking plenty of fluids, which can help ward off both diarrhea and constipation.

Dehydration

Dehydration can be caused by diarrhea or nausea and vomiting, but you could also become dehydrated simply because you don’t feel like you need to drink as much as usual. “These medications reduce appetite not only for food, but some people experience a lower appetite for hydration as well,” says Ortiz-Pujols.

Facial Aging

Stemming, in part, from a rapid loss of fat in the face, some people on a GLP-1 say their facial anatomy looks different, says Criner. Think: hollowed cheeks and temples, sagging skin along the jawline and neck, sunken or dark under-eye circles, and worsened wrinkles.

To sidestep this side effect, Criner recommends aiming for more-gradual weight loss, a protein-rich diet, and good hydration. If you still need help minimizing these facial effects, getting “cosmetic procedures like facial fillers, skin-tightening treatments, or surgical interventions can restore facial volume and manage excess skin,” she says.

Hair Loss

Moreover, the majority of people taking GLP-1 medications do not experience noticeable hair loss, says Brianna Olamiju, MD, a clinical instructor in dermatology at the Icahn School of Medicine at Mount Sinai in New York City. “When it does occur, it is often temporary and most people see regrowth within three to six months,” she says.

While more research needs to be done to explain exactly how GLP-1 drugs may be linked to hair loss, doctors believe one reason is rapid weight loss, which is a well-recognized trigger that puts metabolic stress on the body — a known cause of hair loss, says Dr. Olamiju.

Other possible reasons for hair loss include nutrient deficiencies. “GLP-1 drugs suppress appetite, and if someone isn’t getting enough protein, iron, or other nutrients, they may be more likely to experience hair loss,” says Yolanda Rosi Helfrich, MD, a clinical professor of dermatology and the residency program director of the department of dermatology at the University of Michigan Medical School in Ann Arbor. “Hormonal changes associated with weight loss may also play a role.”

Fatigue and Weakness

These feelings are common the first day or two after taking a dose, but some medications are bigger culprits than others, says Ortiz-Pujols. If you’re noticing debilitating fatigue or weakness, talk to your doctor about decreasing the dose or switching to a new medication, which may help relieve these side effects.

Hypoglycemia

Some people with type 2 diabetes can also develop low blood sugar — typically defined as below 70 milligrams per deciliter (mg/dL) or 3.1 millimoles per liter (mmol/L) — while taking a GLP-1, especially if they’re also on other medications, such as insulin, that can also lower blood sugar levels.

If you’re having frequent drops in blood sugar levels, talk to your doctor, who may recommend lowering the medication dosage. If you do feel hypoglycemic, eat foods with simple sugars, such as a banana, or drink a half cup of apple juice.

Teeth Problems

Because you’re likely eating — and possibly also drinking — less while on a GLP-1, your mouth produces less saliva than usual, says Oritz-Pujols. The resulting dry environment can lead to cavities and gum disease.

Along with drinking enough water, ask your doctor if you should chew sugar-free gum or use a mouthwash designed for dry mouth.

Tips to Reduce Side Effects

Criner advises her patients to increase their intake of dietary fiber, stay hydrated, and use stool softeners to prevent symptoms from worsening.

Ask your doctor what other steps you can take on your own to slash side effects. Things such as reducing meal size, eating only when hungry, and practicing mindfulness while eating, which includes stopping when you feel full, can all help ease gastrointestinal issues, says Criner.

Still, even if you’re doing everything you can to minimize side effects, you may not be able to tolerate that particular GLP-1 forever.

For instance, if you experience acute abdominal pain and are diagnosed with pancreatitis or gastrointestinal obstruction, you should stop taking the medication immediately and not restart it, says Criner. (Physicians will likely stop prescribing a GLP-1 or dual agonist if you receive a pancreatitis diagnosis.) Your doctor should also reevaluate treatment and dosage if you have any other severe side effects.

“More often than not, patients may need to try lower doses of the medication or an alternative class of GLP-1 agonists, as there is a variation in tolerability profile between them,” says Criner.

Ortiz-Pujols agrees, noting that finding the right medication and dosage is likely just a matter of trial and error.

Dive into our GLP-1 resource center for stories on weight loss, medications, side effects, and more.