While many supplement companies carry creatine monohydrate, look for brands that have been tested by third-party organizations such as the Cologne List, NSF International, and the United States Pharmacopeial Convention (USP). This certification ensures that each batch of creatine monohydrate supplement is free of ingredients listed on the Anti-Doping Agency's banned list and what says on the label is what you receive.
One such brand is Creapure, a Cologne-registered German creatine that other supplement brands commonly use with their creatine products.
Want to know what the creatine supplement experts recommend? Here are selections from Antonio and Taylor Wallace, CEOs of the Think Healthy Group and other members of the Forbes Health Advisory Board.
Optimal Nutrition Micro Creatine Capsules
A serving of two capsules contains 2.5 grams of Creapure Creatine Monohydrate. Although research shows that taking creatine directly after exercise helps increase muscle mass, Optimum Nutrition's product packaging says to take two capsules twice daily with food. Experts also differ in timing recommendations.
Bottles contain 100, 200 or 300 capsules. Optimum Nutrition also offers micronized creatine in powder form, which is better for larger servings.
Buy Now: Available with Optimal Nutrition. 
Onnit Creatine Powder
Onnit creatine powder provided by Creapure comes in a 150 gram container with 30 servings per container. Every two tablespoons contains 5 grams of creatine monohydrate.
Use the powder by adding two scoops to your post-workout shake or other favorite drink (see how to take creatine below).
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Pure Athlete Creatine
Wallace recommends Klean Creatine because it is certified by NSF International, the sport's public health and safety organization, as "ideal for competitive athletes". This certification guarantees that the product meets quality standards and does not contain pollutants, banned substances, or masking agents with dangerous levels.
Klean Creatine Creapure powder is tasteless and easy to mix into sports drinks. This product contains 315 grams of powder with 5 grams of creatine monohydrate per serving.
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Naked Nutrition Creatine Monohydrate Powder
This product is certified vegan and gluten-free, making it a great choice for people with dietary restrictions or allergies, says Wallace. The powder comes in a 1 kilogram container and a scoop contains 5 grams of creatine.
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PureAthlete+ Strength
"The Power+ product from PurAthlete is ideal for athletes who want to increase their stamina, strength and endurance," said Wallace. Powder+ is certified by NSF International for Sport®.
Power+ is a creatine-magnesium chelate, which combines the two substances to increase its absorption compared to creatine monohydrate.
This product comes in a 102 gram tube. One scoop contains 290 milligrams of magnesium and 3.3 grams of PurAthlete Performance Blend, which includes MagnaPower Magnesium Creatine Chelate and TRAACS Magnesium Glycinate Chelate.
Because of its high magnesium content, Wallace cautions that consuming three or more servings at a time can have a laxative effect.
BUY NOW: Available on Amazon.