Grotox is Botulinum Toxin Treatment Of The Hyperactive Penile Retraction Reflex. The dartos muscle is responsible for the retraction of the flaccid penis. These contractions are more prominent during exposure to cold and stress or upon exercising. This can be a source of embarrassment to those who have a hyperactive retraction reflex, especially when exposed to their partners or to others in showers and dressing rooms despite a normal and satisfactory length in the erect state. These men are labeled “growers.”
Most are familiar with the scene from Seinfeld where George Costanza is caught with his pants down after swimming in cold water. Shrinkage can happen to some more than others. I’ve been approached by many men who are self-conscious as to how they measure up to their peers in the locker room. They have no frame of reference to how they size up with others in the erect state. They end up comparing themselves with porn stars which is an unrealistic view of the average male. I’ve also had patients contact me because the hyperactive retraction actually causes physical pain.
Grotox, Penile Botulinum Toxin (Botox®, Xeomin®, Dysport®), hopes to spare embarrassment to Growers and alleviate painful retractions. During situations that illicit the retraction reflex, a man’s penis may resemble our turtle pictured in the upper photo. After Grotox, the resting flaccid state is more exterior like the turtle depicted in the lower photo. Botulinum Toxin can allow the penis to hang more thus increasing the flaccid penile length. Erect length, however, remains unaltered.
We inject approximately 25-100u of product into the dartos muscle after achieving adequate numbness from topical local anesthesia. Results do not become apparent until 5-7d after treatment. Follow up is scheduled 1-2 weeks after to determine if more product is required. The reflex is not completely obliterated but blunted. Neuromodulation anywhere on the body typically lasts 3-4 months. Repeat treatments would be needed.