Viagra-like drugs designed to increase sexual pleasure and orgasms may work better for some women than others — depending on the size of their “G spot.”

The area inside the vagina famous for producing incredible orgasms was first dubbed the G spot in 1950. It contains in the Skene’s glands an enzyme called PDE5 which is involved in female arousal.

If the Skene’s glands are large and there is plenty of PDE5, researchers believe Viagra-like drugs should work well but they might be less successful in women with a small G spot.

But even for those with a small G spot or none at all, Viagra-type drugs might have some effect, as PDE5 is found in the clitoris too,” New Scientist magazine said on Wednesday.

Female drugs similar to Viagra, the blockbuster impotence pill that has worked wonders for men, increase sexual pleasure by blocking PDE5, the enzyme that chews up nitric oxide that triggers arousal.

Although scientists knew of nitric oxide activity in the clitoris, Emmanuele Jannini and researchers at the University of Aquila in Italy, found clusters of the PDE5 enzymes in the G spot when they studied 14 cadavers.

But in two other specimens the concentrations of the enzymes were very low and they couldn’t find the Skene’s glands.

“For such women, having a vaginal orgasm is anatomically impossible,” Jannini told the magazine.

But New Scientist said there is still hope on the horizon because scientists are working on drugs that stimulate arousal via the brain.