Introduction

Weight loss medications like Wegovy, Zepbound, Ozempic, and Saxenda can offer life-changing results—but like all powerful medications, they come with potential side effects.
 Knowing what to expect—and how to manage it—can make your weight loss journey smoother and more successful.

In this guide, we’ll cover the common, less common, and rare but serious side effects of today’s top weight loss medications, plus tips for minimizing discomfort.

Why Do Side Effects Happen?

GLP-1 and GIP receptor agonists (like semaglutide and tirzepatide) work by:

• Slowing digestion
• Reducing appetite
• Affecting hormone levels in your brain and gut

These changes promote weight loss but can also temporarily disrupt your digestive system and cause other adjustments as your body adapts.

Common Side Effects (Most Patients Experience)

Symptom	How Common It Is	When It Occurs
Nausea	Very common	First 2–6 weeks
Constipation	Common	Ongoing, varies
Diarrhea	Common	Early, then improves
Fatigue	Mild to moderate	First few weeks
Headache	Mild	Occasionally
Decreased Appetite	Expected	Throughout treatment

Most side effects are mild to moderate and improve as your body adjusts to the medication.

Less Common Side Effects (Monitor But Manageable)

Symptom	Notes
Heartburn or acid reflux	Can happen with slower digestion
Bloating	Usually improves with diet adjustment
Dizziness	Usually from dehydration—stay hydrated
Injection site irritation	Mild redness or discomfort at site

Drinking plenty of water, eating small meals, and avoiding fatty foods can help reduce these symptoms.

Rare But Serious Side Effects (Talk to Your Doctor Immediately)

Serious Issue	What to Watch For
Pancreatitis	Severe stomach pain radiating to back, vomiting
Gallstones	Right upper belly pain after eating fatty foods
Kidney injury	Unusual fatigue, swelling, reduced urination
Thyroid tumors (animal studies)	Unusual neck swelling, trouble swallowing

Patients with a history of MEN-2 syndrome or thyroid cancer should not use GLP-1 medications.

Which Medications Cause the Most Side Effects?

Medication	Side Effect Risk	Notes
Wegovy	Moderate	Nausea common early, usually improves
Zepbound	Moderate to mild	Similar to Wegovy, some fatigue noted
Ozempic	Moderate	Digestive issues early on
Saxenda	Higher	Daily injections linked to more nausea early

Weekly injections like Wegovy and Zepbound are often better tolerated than daily injections like Saxenda.

Tips to Minimize Side Effects

Start Low, Go Slow
 Always follow your provider’s dosing schedule to minimize nausea and digestive upset.

Stay Hydrated
 Dehydration worsens dizziness, fatigue, and constipation.

Eat Small, Low-Fat Meals
 Heavy or greasy foods can trigger nausea.

Rest and Move Carefully
 Fatigue is normal early on; light walking after meals can help digestion.

Communicate With Your Provider
 If symptoms persist beyond 4–6 weeks or feel severe, your provider may adjust your dose or schedule.

When to Call Your Doctor

Contact your healthcare provider immediately if you experience:

• Severe abdominal pain
• Persistent vomiting
• Difficulty swallowing
• Rapid weight loss beyond your doctor’s plan
• Signs of dehydration (dizziness, fainting, dark urine)

Final Thoughts

Side effects are normal and often temporary when starting weight loss medications.
 With proper dosing, hydration, and support, most patients find that side effects improve over time—and the benefits of weight loss far outweigh the early discomfort.

Expect mild digestive symptoms
  Monitor for rare but serious effects
  Stay in close touch with your healthcare provider

For personalized guides on managing side effects and adjusting doses, visit our Medication Support Center.