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You are here: Home / Dietary Supplements / OPSS: Operation Supplement Safety / OPSS: Operation Supplement Safety / OPSS Frequently Asked Questions (FAQs) / Will the dietary supplement product C4 Extreme cause me to “pop positive” on a drug test?


Will the dietary supplement product C4 Extreme cause me to “pop positive” on a drug test?

OPSS Answer

C4 Extreme is marketed by Cellucor as a pre-workout dietary supplement. According to the Supplement Facts on the manufacturer’s website*, it contains vitamins, amino acids, Mucuna pruriens, caffeine, synephrine, and other active ingredients. C4 Extreme is sold in AAFES and GNC stores on military bases, and in response to some concerns expressed by Military Exchanges about drug testing, the makers of Cellucor C4 Extreme submitted samples to an independent analytical laboratory to be tested for the presence of D-amphetamine, a strong stimulant. The resulting lab work provided to the Exchanges revealed that C4 Extreme did not contain D-amphetamine or any other prohibited stimulants that could produce a positive test for D-amphetamine.

None of the ingredients listed on the C4 label should cause a positive drug test. However, there is no way to know what is actually in any specific dietary supplement unless it has been carefully analyzed or third-party certified (please see the OPSS FAQ). Such testing is essentially a snapshot in time of a particular product and is no guarantee that future batches will be the same. As with all dietary supplements, there may be some risk that they contain undeclared ingredients (that is, ingredients not listed on the label), and so it is not possible to predict whether this—or any other—dietary supplement product will cause a positive drug test. For more information on drug testing, please see HPRC’s “Dietary supplements and drug testing.”

*accessed 25 February, 2014

FAQ updated 19 May 2014