GLP-1 Side Effects
Understand common and serious side effects of GLP-1 medications
Gallbladder Problems
SevereRapid weight loss from GLP-1 therapy can increase the risk of gallstones. This is a known risk with any rapid weight loss method, not specific to GLP-1 medications.
Low Blood Sugar (Hypoglycemia)
SevereWhile semaglutide alone rarely causes hypoglycemia, risk increases if combined with insulin or sulfonylureas. Symptoms include dizziness, sweating, confusion, and shakiness.
Abdominal Pain
ModerateAbdominal discomfort or pain is reported by some GLP-1 users, ranging from mild cramping to more significant pain. It is usually related to GI changes.
Facial Volume Loss (Ozempic Face)
ModerateRapid weight loss from GLP-1 medications can cause noticeable facial volume loss, colloquially called "Ozempic face." The face may appear gaunt, hollow, or aged as fat pads in the cheeks and around the eyes shrink.
Hair Loss
ModerateSome GLP-1 users report hair thinning or hair loss, typically occurring 3-6 months after starting treatment. This is usually related to rapid weight loss (telogen effluvium) rather than the medication itself.
Vomiting
ModerateVomiting may occur especially during dose escalation or after eating large or fatty meals. It is related to the slowed gastric emptying caused by GLP-1 medications.
Acid Reflux / GERD
MildGLP-1 medications can worsen or trigger acid reflux (GERD) in some patients due to delayed gastric emptying.
Constipation
MildConstipation is a common GI side effect of GLP-1 medications. The slowed gastric emptying that helps reduce appetite can also slow bowel movements.
Diarrhea
MildDiarrhea is a common gastrointestinal side effect of semaglutide, particularly during the initial weeks of treatment or after dose escalation.
Fatigue
MildFatigue and low energy are common during the initial weeks of GLP-1 therapy. This is often related to reduced caloric intake as appetite decreases.
Headache
MildHeadaches are reported by some GLP-1 users, particularly during the first few weeks. They may be related to changes in blood sugar levels or reduced food intake.
Injection Site Reactions
MildMild reactions at the injection site including redness, swelling, itching, or pain. These are generally harmless and resolve within a few days.
Nausea
MildNausea is the most commonly reported side effect of GLP-1 medications. It typically occurs when starting treatment or increasing the dose and usually improves over time as your body adjusts.