Look at any pure creatine monohydrate (not the ethyl ester or hydrochloride forms) from a reputable supplier. It can cause stomach upsets in some people, but 5 grams once/day is generally well-tolerated and a sufficient dose for almost everyone. Don't expect miracles, but there is good-quality evidence for a marginal increase in sports performance in many situations, for many participants.

I've heard anecdotal reports that it can accelerate hair loss in males (male pattern baldness). I have no clue if this has been studied but enough people have reported it across the web that it has caused me to avoid creatine personally. Any experts here feel like weighing in?

Stronger By Science looked into this and the answer is basically no: https://www.strongerbyscience.com/creatine-hair-loss/

Creatine and caffeine possibly have a negative interaction - search PubMed for papers - eg

https://pubmed.ncbi.nlm.nih.gov/26219105/

I’m very slow and stiff in the mornings and I drink a lot of black coffee to mitigate that.

Then, late afternoon, perhaps 6 to hours later, I take my creatine monohydrate for the day just before my ocean swim.

Make sure to eat food before you take it, and start with 2.5g twice a day instead of 5g all at once to go easy on your stomach. The food helps slow down how quickly the creatine moves through your system. This prevents too much water from being pulled into your GI tract, avoiding undesirable symptoms (use your imagination).

As more anecdata, I eat it all times of the day and have no undesirable symptoms, before food, after food, while not eating at all, it simply doesn't have enough impact on the stomach for me to notice.

I get that it might treat people differently. This is what works for me, otherwise I wouldn’t be able to take it at all.

This is likely a complete coincidence, so take my experience with a grain of salt. However… I am somewhat convinced that creatine caused me to develop appendicitis last summer about 5 days into a supplementation cycle. My best guess is that increased fluid retention (caused by creatine) caused vascular congestion at the verniform appendix.

On the (monkey’s paw) plus side, the perioperative IV fluids plumped up my muscles and gave a muscle man appearance that I was after for several days. I believe I was up 10-15 lbs in water weight when I came home.

Buy Thorne if you are really concerned about quality. Otherwise bulk supplements is fine. Creatine monohydrate is cheap and easy to produce

Be prepared to up your water intake significantly. In particular, I started sleeping near a full bottle of water.

I assume you're aware of the water weight gain. Otherwise, it's effects are fairly modest.

I don't know the first thing about these authors or if this paper was funded by a supplement company... but apparently that is a myth[1]? You may gain some water weight for a week or two, but that seems to stop.

[1]: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7871530/

You gain a few pounds of water weight during the "loading" phase (the entire idea is that it's drawing water and metabolic fuel into the muscles) and then it plateaus as long as you keep taking it. When you stop taking it, the water weight will come off.

I workout seriously enough that people notice if that means anything, and I take creatine. It's one of those things with the most proven upsides and essentially no downsides. That said, the effects are nothing like serious PEDs - not that I can personally compare those things, but it's quite clear that gear is a whole other level.

I just started taking creatine in the morning with my coffee and gained +1kg. My weight is incredibly stable, but creatine did a small hit. 84kg to 85kg

Just a note here: after another week my weight returned to normal. Might be the increased training, but whatever

Start now, don't overthink it. It's one of (if not the most) studied supplements on the market.

just buy any monohydrate. if youre paranoid, look for a brand with cgmp certification thats batch tested.

other than that, dont expect a large effect. many people dont respond, and the rest get a small benefit plus a bunch of placebo effect.

Drink water when taking creatine and maybe while eating something, or it can lead to mild stomach discomfort.

I like the crystalline stuff rather than the powdery stuff because when I mix creatine with a juice the powdery stuff tastes worse, probably because the crystals just float past your tongue and you barely taste it.

My fav way to take it is put a tablespoon of crystals in about 3 fingers of juice, swirl the cup with the wrist and sip, swirl and sip, swirl and sip, until its all gone.