Research has shown that Epimedium extract can inhibit an enzyme called acetylcholinesterase (AChE). AChE rapidly stops neurotransmission at cholinergic synapses like those found in the brain and at neuromuscular junctions, which are needed for speedy responses in the neuromuscular system. By inhibiting AChE, Horny Goat Weed supports higher levels of the key cholinergic neurotransmitters associated with sexual arousal.