Synergistic enhancers of antiretrovirals usually do not possess any antiretroviral properties alone, but when they are taken concurrently with antiretroviral drugs they enhance the effect of that drug.
[1] One of these is an over-the-counter nutritional supplement and another two of these have been FDA approved (for other indications).
The effects of these drugs, however, will require further evaluation before being clinically exploited.
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