Clinical strength indicates a more potent mixture of active sweat blocking ingredients. For example, you’ll typically find a much higher percentage of Aluminum in a clinical strength antiperspirant vs. a standard supermarket antiperspirant. The increased active ingredient usually results in an increased and sometimes prolonged effectiveness. Prescription strength antiperspirants are also available if you have been diagnosed with severe hyperhidrosis (excessive sweating). Like most prescription medications, a prescription antiperspirant can have a nasty list of side effects, including itching, redness, burning, rashes, etc… Before using a potentially dangerous medication to treat your sweating problem, try a strong clinical strength antiperspirant like SweatBlock… wink, wink.