A Ukip candidate recently resigned after making racist and homophobic comments . The excuse offered was that this was due to his being under the influence of prescription medication. Many have scoffed at this explanation, but is there any scientific basis to the claim that painkillers can cause racism or other bigotry?

Ukip candidate Kerry Smith has not had a good week. He has resigned after it was revealed he had made several alarmingly offensive comments about homosexuals and Chinese people. This is, depressingly, nothing new; hearing that Ukip has done or said something offensive and or/ridiculous is basically the modern news equivalent of a screensaver, something that pops up if you stop looking at anything else for a few seconds.

But what’s interesting about this story is the excuse offered; Mr Smith apparently made his comments because he was under stress and, more bizarrely, the influence of prescription medication. This has been roundly dismissed in the face of scientific evidence. However, people are very quick to rule out Ukip’s claims as having any worth, but is this fair? After all, these claims are largely consistent with Nigel Farage’s assertion that tiredness causes racism. And remember when a Ukip councillor was widely mocked for claiming same-sex marriage caused floods? Turns out there may have been something to this after all.

So perhaps painkillers or sedatives (it’s unclear which was responsible from reports) don’t cause racism or bigotry directly, but is there not some other mechanism by which someone could become more openly prejudiced due to such medications? Here are a few possibilities.

The pain of tolerance

One of the simplest explanations for Mr Smith’s claims is that the pain he was taking medication for was somehow linked to racist thoughts and behaviour. An obvious conclusion is that the pain he was experiencing actually prevented him being racist, so once it was relieved there was nothing preventing it from manifesting?

While there are many complex psychological processes underpinning racism, it is possible that Mr Smith’s pain was acquired in such a manner that directly linked it to racism. The exact nature of the pain-causing injury hasn’t been revealed (that I’ve seen) but it’s easy to speculate how it may have been associated with prejudiced behaviour. Perhaps he was driving and spotted a family of Muslims, prompting him to angrily shake his fist at them and lose control of the vehicle? Or maybe he put his back out while putting up some of Ukip’s more dubious posters?

The association of behaviour with unpleasant stimulus is a well-established psychological technique known as aversion therapy, but if the pain-associated-with-racism was constant then as soon as it was lessened it could have caused an outpouring of the unpleasant thoughts that had recently been bottled up?

Distressing dissonance

Perhaps Mr Smith’s pain was caused by mishaps totally unrelated to prejudiced behaviours. But given that he was on prescription medication it is safe to assume his injury was treated by medical professionals. It’s highly likely he was seen by a doctor in the NHS, but there’s a 26% chance that this doctor was a foreign national. If you are someone who’s fundamentally opposed to foreigners working in the UK but then you let one treat you and they relieve your suffering, this will undoubtedly cause some serious cognitive dissonance. Cognitive dissonance can cause some serious discomfort, anxiety and stress (and Mr Smith did say he was under stress at the time, so that further supports this possibility).

Anxiety and stress can be treated with sedatives, so although the dissonance wouldn’t have been resolved by the medication, the discomfort that it causes will have been lessened or removed, thus allowing more “consistent” behaviour.

Avoid the opioids

It may be that the confusion around the precise nature of the medication Mr Smith was on is due to the fact that it was a powerful opioid. Opioids, the family of drugs that includes morphine and heroin, are known as potent painkillers, but can also have sedative effects. So if Mr Smith was taking opioids, both effects mentioned above could well have been in play. A powerful dose of drugs running through your system will alter anyone’s behaviour, but as has been stated, there’s no known drug that actually induces bigoted behaviour, it has to be pre-existing for such a thing to occur.

But high-levels of sedation can render a person more suggestive and less inhibited, and high opioid doses can lead to hallucinations. Perhaps spending so much time among the upper-echelons of Ukip exposed Mr Smith to a lot of “questionable” views and opinions, and his medication caused them all to seem more salient to him at the time of his unfortunate outbursts?

But it’s also worth mentioning that opioids can cause constipation. This is unpleasant at the best of times, but for someone deeply involved in UKIP it could be catastrophic, given how full of crap they can be. Perhaps the pressure just got too much?

Dean Burnett has many ridiculous views of his own. You can see them on Twitter. @garwboy