GLP-1 side effects, explained
Most patients tolerate semaglutide and tirzepatide well — but the side effects can feel surprising the first few weeks. Here's the playbook.
Nausea
Most common. Worse in the first week of a dose increase. Eat smaller meals, avoid greasy/fried foods, and stop eating when you feel full — not when the plate is empty.
Constipation
Caused by slowed gastric emptying. Fix it with water, fiber, magnesium citrate, or a stool softener. Call your pharmacist if it lasts more than a few days.
Fatigue
Usually a side effect of eating less, not the medication itself. Make sure you're hitting protein targets (0.6–1 g per pound goal body weight).
Acid reflux
Manage with H2 blockers or PPIs. Don't lie down within 2 hours of eating.
Serious effects
Rare but real: pancreatitis (severe abdominal pain), gallbladder issues, and (very rarely) thyroid concerns. Call your pharmacist or prescriber for severe abdominal pain, persistent vomiting, or yellowing of the skin/eyes.
When in doubt — call us
Parkway Metabolic Health includes pharmacist coaching specifically to manage these side effects. Most issues are solvable with a dose-pace change, hydration, or a simple OTC fix.
Have questions for a pharmacist?
Parkway pharmacists are available by phone or in person — no appointment required.