The drug that most affects sexual arousal in men is alcohol, a new study has found.

Furthermore, quitting drinking may not solve the problem.

Spanish and Columbian scientists looked at over 900 men, 550 of whom had been diagnosed with an addiction to either alcohol, cocaine, alcohol and cocaine, marijuana, heroin or heroin and cocaine.

The sexual performance of all the men was assessed. Performance was divided into four categories - sexual desire, sexual arousal, sexual satisfaction and orgasm.

The scientists looked at the effects the different drugs had on each category.

The study found that overall, the sexual performance of those using drugs was moderately to significantly impaired compared to those who did not use drugs.

Different drugs had different effects on the various categories. For example, cocaine use did not usually affect sexual desire, but did affect sexual pleasure. Meanwhile, cocaine, heroin and alcohol all affected the ability to orgasm.

When it came to sexual arousal, alcohol had the biggest detrimental affect. And this problem did not appear to resolve even if the men stopped drinking. This contradicts other studies which indicate that sexual performance returns to normal a few weeks after quitting drugs.