# GLP-1 Side Effects: Manage Nausea & Fatigue · PH Peptides Source: https://www.philippinespeptides.com/guides/glp1-side-effects Updated: 2026-11-03 > Practical management protocol for GLP-1 side effects on Retatrutide, Tirzepatide, and Semaglutide. On this page - [Why Side Effects Happen](#why) - [Frequency Overview](#overview) - [Managing Nausea](#nausea) - [Managing Constipation](#constipation) - [Managing Fatigue](#fatigue) - [Decreased Appetite](#appetite) - [Injection Site](#injection) - [Rare Serious](#serious) - [Adjustment Timeline](#timeline) # GLP-1 side effects: a management protocol Philippines Peptides editorial desk Updated 3 November 2026 4 min read **Compounds** - Reta · Tirz · Sema **Peak window** - Weeks 1 – 4 **Nausea rate** - 40 – 50% **Constipation** - 25 – 30% **Fatigue early** - 20 – 30% **Resolves by** - Wk 4 – 6 Sourcing note: most readers of this site buy retatrutide from Primara Labs, our partner and supplier. Stock sits inside the Philippines, vials are batch-numbered, and Metro Manila orders verified before noon go out the same day. [Retatrutide price Philippines](https://www.primaralabs.com/marketplace/retatrutide?utm_source=philippinespeptides&utm_medium=referral&utm_campaign=inline&utm_content=glp1-side-effects) ## Why side effects happen GLP-1 peptides ([Retatrutide](https://www.philippinespeptides.com/peptides/retatrutide), [Tirzepatide](https://www.philippinespeptides.com/peptides/tirzepatide), [Semaglutide](https://www.philippinespeptides.com/peptides/semaglutide)) work by mimicking a hormone your body naturally produces. Introducing it externally at higher levels means your body needs time to adjust. Most side effects are gastrointestinal: your gut adapting to slower gastric emptying, reduced appetite signals, and changes in digestive motility. Good news ## Frequency overview | Side effect | Frequency | Usually resolves by | | --- | --- | --- | | Nausea | Very common (40 – 50%) | Week 4 – 6 | | Decreased appetite | Expected | Ongoing | | Constipation | Common (25 – 30%) | Week 4 – 8 | | Diarrhea | Occasional (10 – 15%) | Week 2 – 4 | | Fatigue | Common (20 – 30%) | Week 3 – 4 | | Headache | Occasional (10 – 15%) | Week 2 – 3 | | Injection site | Occasional (5 – 10%) | Improves with technique | ## Managing nausea Nausea is the #1 complaint, especially during titration. GLP-1s slow down how quickly food leaves your stomach. Eat too much or too fast and food sits there longer, causing nausea. Eat smaller meals Your stomach can't handle the same volume anymore. Half portions, more frequently. Eat slowly Take 20 – 30 minutes per meal. Put your fork down between bites. Avoid trigger foods High-fat, greasy, processed foods are the worst. Stick to lean proteins and vegetables initially. Stay upright after eating Don't lie down for at least 2 hours after meals. Ginger Ginger tea, ginger chews, or supplements genuinely help. Keep them on hand. Titrate slowly If nausea is severe, stay at your current dose for an extra week before increasing. There's no rush. Time your injection Some users find nausea is worse 24 – 48 hours post-injection. Try injecting Friday evening so the worst passes over the weekend. When to seek medical attention ## Managing constipation Slower gut motility plus eating less equals less frequent bowel movements. Normal but uncomfortable. Fiber supplementation Psyllium husk (Metamucil) or similar. Start with half the recommended dose. Hydration At least 2 – 3 liters of water daily. Dehydration makes constipation significantly worse. Magnesium Magnesium citrate or glycinate (200 – 400mg at night). Gentle stool softener that many GLP-1 users rely on. Movement Even a 20-minute walk stimulates gut motility. Coffee If you drink coffee, don't stop. It's a natural gut stimulant. ## Managing fatigue Some users feel unusually tired in the first few weeks, especially with retatrutide which increases metabolic demand via glucagon activation. Ensure adequate calories Don't go too low too fast. Even with reduced appetite, aim for at least 1200 – 1500 calories daily. Prioritize protein Sustained energy and muscle preservation. Aim for 1.6g per kg of bodyweight. Electrolytes Sodium, potassium, magnesium. Especially important in the Philippines climate. Sleep Your body is doing extra work adapting to a new metabolic state. Give it extra rest. ## Decreased appetite This is the intended effect, but if appetite is completely gone, you risk muscle loss, deficiencies, and fatigue. Schedule meals Even if you're not hungry, eat at set times. Treat it like medicine. Prioritize protein If you can only eat one thing, make it protein. Protein shakes When solid food feels impossible, a shake is easier and ensures you hit targets. Track intake Use MyFitnessPal for the first few weeks to make sure you're eating enough. | Nutrient | Minimum daily | | --- | --- | | Protein | 1.2 – 1.6g per kg bodyweight | | Calories (women) | 1,200 – 1,500 | | Calories (men) | 1,500 – 1,800 | | Water | 2 – 3 liters | ## Injection site reactions Rotate sites Different spot each week: abdomen (left and right of navel), thighs, back of arms. Proper technique 90° angle into pinched fat. Push plunger slowly. Let alcohol dry After swabbing, wait 10 seconds before injecting. Don't massage Just remove the needle. Do not rub the site. Room temperature Let the peptide sit 5 – 10 minutes after removing from the fridge. Cold injections are more irritating. ## Rare but serious Pancreatitis Gallbladder issues ## The adjustment timeline | Week | What to expect | | --- | --- | | 1 – 2 | Side effects peak. Nausea, fatigue common. This is normal. | | 3 – 4 | Side effects begin improving. Energy returns. Appetite shift feels more natural. | | 5 – 8 | Most side effects resolved. Titration may cause temporary return of mild nausea. | | 8+ | Smooth sailing for most users. Side effects minimal if present at all. | Our partner and supplier ### Ready to order retatrutide? Primara Labs, our partner and supplier, holds stock inside the Philippines. Vials are batch-numbered, Metro Manila orders verified before noon dispatch the same day, provincial couriers run 1 to 3 days, and every order gets 10% off. --- Philippines Peptides sells nothing. Primara Labs is our partner and supplier. This is general information, not medical or legal advice.