I've been lifting on Mounjaro for 5 months and want to add creatine to my supplement stack. But I keep seeing conflicting info — some people say it's fine, others say it "messes with your kidneys" or "causes water retention that masks weight loss" or whatever.

Can we have an evidence-based discussion about this? Specifically:

1. Is creatine safe to take alongside GLP-1 receptor agonists?
2. Does the water retention issue actually matter?
3. Standard dosing — is 5g/day still the recommendation?
4. Any GLP-1-specific considerations?

Would love to hear from anyone with actual knowledge rather than bro-science fear mongering.

Happy to weigh in on this. Creatine monohydrate is probably the single most studied supplement in sports nutrition history, with an extremely robust safety profile.

1. Safety with GLP-1 agonists: There is no known pharmacological interaction between creatine monohydrate and semaglutide/tirzepatide. They work through entirely different mechanisms. Creatine is stored in skeletal muscle; GLP-1 agonists work on incretin receptors. No contraindication.

2. Water retention: Yes, creatine causes intracellular water retention — typically 1-3kg in the first 1-2 weeks (the "loading" phase, though loading isn't necessary). This is INTRACELLULAR water pulled into muscle cells, which is actually beneficial for muscle protein synthesis. It is NOT subcutaneous water retention (bloating). However, if you're tracking weight loss on a scale, expect a temporary "stall" or slight increase when you start. This is not fat gain. Use waist measurements or DEXA alongside the scale.

3. Dosing: 5g/day of creatine monohydrate. Every day, not just training days. No loading phase necessary — you'll saturate stores in ~3-4 weeks at 5g/day vs ~1 week with a 20g/day load. The loading phase can cause GI distress, which is the LAST thing you need on GLP-1 meds.

4. GLP-1-specific considerations:

• Skip the loading phase (see above — GI risk)
• Take it with food if possible to improve absorption and reduce any stomach upset
• Creatine monohydrate, not HCL or other fancy forms — mono has the most evidence
• Stay well hydrated — you should be doing this anyway on GLP-1 but creatine increases the need

The kidney myth: Creatine does increase creatinine levels in blood tests, which can look like impaired kidney function to an uninformed clinician. If you're getting bloodwork, tell your doctor you take creatine so they don't misinterpret the results. Actual kidney damage from creatine in healthy individuals has never been demonstrated in clinical research.

But my doctor told me creatine is "hard on the kidneys" and I shouldn't take it especially while on medication... 😟 Now I don't know who to believe.

With respect to your doctor — many general practitioners are not up to date on sports nutrition research. The "creatine = kidney damage" myth has been thoroughly debunked in the literature. The International Society of Sports Nutrition published a position stand in 2017 explicitly stating that creatine monohydrate is safe for healthy individuals at recommended doses.

However — and this is important — if you have pre-existing kidney disease or impaired kidney function, that's a different conversation entirely. In that case, your doctor's caution is warranted and you should follow their guidance.

For healthy individuals with normal kidney function? The evidence is overwhelming that 3-5g/day is safe, even long-term.

Been taking 5g creatine daily for 3 months now alongside Ozempic 1.0mg. Here's my real-world experience:

• Scale went up 1.8kg in the first 10 days — expected water retention, didn't panic
• After that initial bump, weight loss continued at the same rate as before
• Strength gains have been noticeably better — added 5kg to my bench in a month vs the usual 2.5kg pace
• Zero GI issues (I take it with breakfast, no loading phase)
• Bloodwork at month 2 — creatinine was slightly elevated but my doctor was aware and wasn't concerned

Honestly wish I'd started it from day one. It's cheap, effective, and well-studied. The 5g/day protocol is as simple as it gets.