If you’ve ever had a dodgy knee or a kidney stone, chances are that you’ve been prescribed anti-inflammatory medication to ease the pain. It’s quite likely that your GP’s treatment of choice was diclofenac. And very effective it is too.

 Not so good, though, if you’re any one of the three species of Gyps vultures from South Asia, and you feast on the carcasses of cattle that have been treated with the drug.

Cattle? With dodgy knees? Taking drugs? Well, possibly. For religious reasons, dying cattle are not killed to relieve their suffering in some countries, so they are sometimes given painkilling medication instead. Diclofenac, though, has been banned as a veterinary drug in India, Pakistan and Nepal since 2006, and for very good reason.

Populations of the Indian, slender-billed and white-rumped vultures have crashed dramatically since the 1990s. When I say dramatically, I’m not exaggerating. The first two species have declined by 97% during the past decade, and the third by as much as 99.9%. And diclofenac is thought to have been the primary cause.

Wait, I hear you ask, vultures are taking diclofenac? Do they have dodgy knees? No, of course not – but dying cattle have been given it, and there’s nothing an Asian vulture likes more than a dinner of recently deceased raw cow. If this dinner was recently treated with diclofenac, then it’s poisonous to an unsuspecting vulture, often fatally so.

The ban in 2006 was a step in the right direction. But a new study, published in the journal Oryx, has revealed the shocking truth that over one-third of Indian pharmacies are flouting the ban and continuing to sell the drug for veterinary use. A survey of 250 chemists’ shops in 11 Indian states, conducted between 2007 and 2010, found that 36% were selling diclofenac, despite being told that it would be used for treating cattle. The drug was often sold in large containers, so could not have been intended for human use.

Preventing the sale and use of diclofenac is the major challenge in the fight to bring these amazing vultures back from the brink of extinction. The new organisation Saving  Asia’s Vultures from Extinction (SAVE) is leading the fightback, managing three breeding centres in India, where 271 vultures are being housed as part of an increasingly successful breeding programme.

Remember those mop-top vultures in Disney’s Jungle Book? The ones that bore a suspicious resemblance to The Beatles? You may remember that they sung “That’s What Friends Are For” to Mowgli. Certainly the Asian vultures are in need of a few friends right now....