Poppers

Studies show men who sniff poppers when getting fucked without a condom are more likely to get HIV (compared to men who do the same thing but without poppers). Just how isn't fully understood but possible reasons are:

• Poppers relax the muscle that the walls of blood vessels are made from. This opens them more, making more blood flow into the arse. As blood vessels relax and expand they get bigger and thinner. This might make it easier for HIV to get through them. It might also make blood vessels more likely to break then bleed during anal sex. Both of these could make it easier for HIV to enter a man's bloodstream if he gets fucked without a condom.
• Because poppers relax the muscle in the sphincter making it easier to be fucked, fisted or take sex toys, men who use poppers might be more likely to have rougher sex with more bleeding.
• Researchers think poppers might weaken the immune system for a few days, leaving someone more open to picking up HIV.

New research suggests sniffing poppers during sex makes it much more likely HIV is passed on. Neil Macdonald from Imperial College, London talks about what his work has uncovered.

Neil, can you tell us about your research?

It's called INSIGHT and it was carried out by the Medical Research Council. We interviewed 75 men who had recently tested HIV positive and 157 men who'd recently tested HIV negative at sexual health clinics in London, Brighton and Manchester. They'd all tested HIV negative in the previous two years. We wanted to know what they'd done in between these tests that lead to some getting HIV when others didn't.

Any surprising findings?

Well, it was no surprise that men who tested positive were more likely than the negative men to have been fucked without a condom. A big surprise was poppers. Men who tested positive were much more likely to have used them than the guys that stayed HIV negative. When we took into account men's risky sexual behaviour, of the drugs men took only poppers showed an additional risk.

Are we talking about a small increase in risk?

No, it's a big one. 80% of men who tested HIV positive used poppers compared to 58% who stayed negative. When we looked at men who'd been fucked without a condom by someone they didn't know was HIV negative, 61% of the men who tested positive had sniffed poppers - compared to 32% of men who'd stayed negative.

Should we be surprised at what you found?

Well, there have been quite a few studies over the years suggesting that poppers are a risk factor for HIV. When you think about it, poppers are the only drug that causes a major change to the inside of our arses. They increase the blood supply to the area, expanding blood vessels, which might make them more likely to bleed. An unsafe fuck is already risky but it's easy to see how poppers could make it even more risky. Also, some scientists think poppers might affect the immune system.

Any other thoughts on poppers?

There might be other ways poppers increase the risk. Maybe they make rougher fucking easier. Maybe poppers are more likely to be used by men who like a rougher kind of sex. But what we do know is that unprotected sex where poppers are sniffed makes a man more at risk of getting HIV.

Finally, anything else you'd like to tell us about?

It was clear from INSIGHT that the men who consistently used condoms, even those that used poppers, didn't get HIV. They really are our best defence.

We'd also like to take this opportunity to thank all the men that took part in the study.

For more on the INSIGHT study, including more about HIV and poppers, call THT Direct on 0808 802 1221 or click here to download a Sector Summary Report on poppers.

• This article was last reviewed on: 18/10/11
• Date due for next review: 18/10/13