According to the BBC (and many others)...

Libido problems 'brain not mind'

Scans appear to show differences in brain functioning in women with persistently low sex drives, claim researchers.

The US scientists behind the study suggest it provides solid evidence that the problem can have a physical origin.

The research in question (which hasn't been published yet) has been covered very well over at The Neurocritic. Basically the authors took some women with a diagnosis of "Hypoactive Sexual Desire Disorder" (HSDD), and some normal women, put them in an fMRI scanner and showed them porn. Different areas of the brain lit up.

So what? For starters we have no idea if these differences are real or not because the study only had a tiny 7 normal women, although strangely, it included a full 19 women with HSDD. Maybe they had difficulty finding women with healthy appetites in Detroit?

Either way, a study is only as big as its smallest group so this was tiny. We're also not told anything about the stats they used so for all we know they could have used the kind that give you "results" if you use them on a dead fish.

But let's grant that the results are valid. This doesn't tell us anything we didn't already know. We know the women differ in their sexual responses - because that's the whole point of the study. And we know that this must be something to do with their brain, because the brain is where sexual responses, and every other mental event, happen.

So we already know that HSDD "has a physical origin", but only in the sense that everything does; being a Democrat or a Republican has a physical origin; being Christian or Muslim has a physical origin; speaking French as opposed to English has a physical origin; etc. etc. None of which is interesting or surprising in the slightest.

The point is that the fact that something is physical doesn't stop it being also psychological. Because psychology happens in the brain. Suppose you see a massive bear roaring and charging towards you, and as a result, you feel scared. The fear has a physical basis, and plenty of physical correlates like raised blood pressure, adrenaline release, etc.

But if someone asks "Why are you scared?", you would answer "Because there's a bear about to eat us", and you'd be right. Someone who came along and said, no, your anxiety is purely physical - I can measure all these physiological differences between you and a normal person - would be an idiot (and eaten).

Now sometimes anxiety is "purely physical" i.e. if you have a seizure which affects certain parts of the temporal lobe, you may experience panic and anxiety as a direct result of the abnormal brain activity. In that case the fear has a physiological cause, as well as a physiological basis.

Maybe "HSDD" has a physiological cause. I'm sure it sometimes does; it would be very weird if it didn't in some cases because physiology can cause all kinds of problems. But fMRI scans don't tell us anything about that.

Link: I've written about HSDD before in the context of flibanserin, a drug which was supposed to treat it (but didn't). Also, as always, British humour website The Daily Mash hit this one on the head...

It's not been a great day for Germany. First, they lost to Serbia in the footy. Then German pharmaceutical company Boehringer Ingelheim suffered an equally vexing setback after their allegedly libido-boosting new drug, flibanserin, failed to get approval to be sold in the US.

The FDA panel's unanimous decision was no surprise to anyone who read their briefing report which came a few days ago (here) as it was pretty scathing about the strength of the evidence that Boehringer submitted in support of the drug's efficacy. Take this bit (from page 38)

Ouch. Basically, the FDA concluded that as an aphrodisiac it doesn't work very well, if at all, and hence it can't be considered an efficacious treatment. For more background on flibanserin see my old post here and more recently Petra Boynton's excellent coverage.

But what was flibanserin supposed to treat in the first place? Something called "hypoactive sexual desire disorder" (HSDD). What is hypoactive sexual desi...oh, hang on. I think I can work it out. It's a disorder where you have hypoactive sexual desire. The clue is in the name.

The truth of course is that it's more than a clue: HSDD is nothing more than its name. And in fact, the "disorder" bit is entirely superfluous, and the "hypoactive" is needlessly technical. HSDD is simply a description for low sexual desire.

As such, it is wrong to say that it doesn't exist - clearly some people do have low sexual desire, and some of them (though not all) would prefer to have more. But giving it a fancy name and calling it a disorder is entirely misleading: it gives the impression of depth (i.e. that this is some kind of medical illness) when in fact it is simply describing a surface phenomena, like saying "I'm bored" or "I'm tired".

Psychiatry - or more specifically the DSM-IV textbook of the American Psychiatric Association - is chock full of these the-clue-is-in-the-name disorders. Essentially, if the symptoms of the condition are simply summarized in the name, it's almost certainly of this type. You have "Generalized Anxiety Disorder" if you're... generally anxious. According to the next DSM-5, your kid will have "Temper Regulation Disorder with Dysphoria" if... oh, guess.

Not all psychiatric disorders are like this though. The word "Schizophrenia" is just a name: it describes a cluster of quite diverse symptoms that are not contained in the name (and indeed if you take the name literally you would end up with entirely the wrong idea.) Likewise for "Bipolar Disorder" and "Depression".

These are names for groups of symptoms which tend to go together and saying that someone has "Depression" tells you several different things about them - e.g. that they have low mood, certain kinds of sleep disturbance and appetite disturbance, etc. In fact not everyone shows all of these all the time, but most people show most of them.

The point is that to diagnose someone with, say, schizophrenia, on the basis that, say, they believe an alien is controlling their thoughts through a radio in their head, is to assert something about them; it might be a correct diagnosis, or it might be wrong e.g. they could in fact be bipolar, or it could be a culturally based belief, or they might even be right.

But if you "diagnose" someone with HSDD, you cannot be wrong - assuming they have told you that they have low sexual desire, which is the only possible reason you would make that "diagnosis". HSDD is just a re-description of their complaint. Yet it also smuggles in the implication that behind the complaint is a medical problem which could be treated with drugs.

Now maybe that's right. Maybe it isn't. We just don't know. It doesn't appear to be treatable with flibanserin. But then, maybe that's because it's not a medical issue at all in most cases.

Suppose there was someone who's perfectly healthy, just stressed, or worried, or or unhappy.

And suppose that, for whatever reason, they go see their doctor about their problems, they get a diagnosis of depression, or social anxiety disorder, or something, and a prescription for Prozac.

What's wrong with this picture? Well, it's a clear case of medicalization: because I made it up to be a good example of medicalization. But what's wrong with medicalization? The medicines themselves? Many people think so, but if you ask me, they're the least troublesome part of the process.

Drugs cost money, but not much: generic fluoxetine, i.e. non-brand-name Prozac, currently costs less than 10 cents per day. Drugs have side effects, but if our hypothetical person doesn't like the Prozac he or she's been prescribed, there's nothing stopping them from chucking it in the bin.

A diagnosis, on the other hand, is a lot harder to shake. In theory, one could get a second opinion from a different doctor and be declared perfectly healthy but in all my conversations with psychiatrists and patients I've never known of someone with a mental health diagnosis getting "undiagnosed" completely.

What's harmful about a mental health diagnosis? It changes the way you think about yourself, in many complicated ways. Just for one thing, it's likely to make you reconsider your past actions and ask if they were "really you", or whether they were caused by your illness.

Now, if you really are mentally ill, that is, if the diagnosis is accurate, this change will probably be a good thing; it might help you realize that with help, you can change, and avoid making the same mistakes you blame yourself for, for example. But if you're not ill, the same changes might be harmful.

A diagnosis invites you to think about problems through the lens of objective, impersonal analysis and treatment, what we might call the "clinical approach". The clinical approach is obviously the best one for most physical diseases. If you have cholera, you are ill, and you need to be diagnosed, and treated appropriately. Most people would agree that the clinical approach is also useful, albeit more problematic, in clear cut mental illnesses like schizophrenia, bipolar disorder, and (some cases of) depression.

But if your problem, or the root of your problems, is not that you're ill but that you're poor, or a victim of discrimination, or in the wrong job, or the wrong relationship, or you don't have either, etc. then a diagnosis is both futile, and quite possibly, actively harmful.

Futile because there's no disease to treat, and harmful because by situating that the origins of your problems are inside yourself (your neurochemistry, a "chemical imbalance"), it diverts attention from the real issues and the real solutions. Maybe you just need to change your situation, take a decision, get a new perspective, stop doing something.


Is there an answer? Many people want us to stop taking so many antidepressants: reverse the trend of medicalization, by reducing the number of pills we take. But there may be another way: commercialization.

Suppose that you didn't need a prescription to get Prozac: you just bought SSRIs over the counter, like aspirin, whenever you felt like it. What would this mean? It might mean more people taking Prozac, although I'm not sure it would. But it would almost certainly change the way people think about antidepressants.

Commercializing SSRIs would, I think, mean that many SSRI users stopped seeing themselves as "psychiatric patients", or as the pills as cures for their "illnesses". Instead they'd see them more like aspirin, or coffee, or beer: something to help you "feel better", a nice thing to have in some circumstances, but not something that's going to solve all your problems. It would, in other words, prevent mentally healthy people from thinking of themselves as "mentally ill". With any luck, our hypothetical friend from the first paragraph would be one of them.

Of course, this would be no benefit if you think that the whole problem with Prozac is the actual drug, fluoxetine hydrochloride. But if, like me, you think fluoxetine hydrochloride is pretty benign compared to the idea of Prozac, it would be a good move. The good thing about commercialization is that it makes it easy to buy things without having to think about them.


You can easily take this argument too far, and if you do, you'll eventually arrive approximately here. Don't. Serious clinical depression and anxiety disorders are real, and people who suffer from them often need "prescription-strength" drugs, and more importantly, professional help rather than being left to self-treat, because the ability to take care of yourself is, almost by definition, impaired in mental illness.

But these people might benefit from the commercialization of mood as well. They'd no longer be seen as qualitatively different from everyone else, weird and unusual. It's like how if someone's got severe pain, and needs prescription-strength painkillers, that's no big deal, because hey, we've all taken aspirin for headaches.


Commercialization would be better than medicalization for other drugs too. Take flibanserin, the new drug for "Hypoactive Sexual Desire Disorder", a condition which, according to the drug company who make flibanserin, affects maybe 20% of women.

Whether flibanserin really boosts libido to any significant extent is unclear, but let's assume it does. Why not sell it over-the-counter? Give it a raunchy name, put it in a colorful box, and sell it in pharmacies next to the condoms. I can picture it now...

Now that would be pretty ridiculous. It would be a crass example of the commercialization of sexuality. But flibanserin already is - or at least, saying 20% of women ought to be taking it is. By selling it as a lifestyle product, instead of a medical treatment, its crassness would be obvious, and we'd just have lots of people taking flibanserin, instead of lots of people taking flibanserin and thinking of themselves as suffering from "Hypoactive Sexual Desire Disorder" i.e. a mental illness.

Unfortunately, I rather doubt that this is going to happen any time soon, although if you go to many "3rd world" countries, you'll find antidepressants, and indeed most other drugs, on the pharmacy shelves for anyone to buy without a prescription. To Westerners, this might seem primitive. I'm not so sure.

It's every man's dream - a pill to make women want more sex. According to Boehringer Pharmaceuticals, that dream could be a reality in a few years, in the form of the strangely-named flibanserin. But is it the latest wonder-drug or just a glorified sleeping pill? Read on.

Flibanserin was originally developed as an antidepressant, but in clinical trials against depression it reportedly failed to perform better than placebo. The standard for getting approved as an antidepressant is low, so this is quite an achievement.

The BBC today described flibanserin as the "Female Viagra", which is rather confusing, because it's meant to increase sexual desire, which is one thing Viagra (sidenafil) doesn't do. The reason for the Female Viagra headline is that, as Professor John Thorp says:

"It's essentially a Viagra-like drug for women in that diminished desire or libido is the most common feminine sexual problem, like erectile dysfunction is in men"

Yes, one in ten women suffer apparently from "Hypoactive Sexual Desire Disorder" (HSDD) as Boehringer Pharmaceuticals helpfully informs us. And “As many as two out of every 10 women describe some degree of decreased sexual desire" according to the unfortunately named Dr Charles de Wet, Boehringer medical director for the UK.

HSDD is a diagnosis in the DSM-IV, the American Psychiatric Association's listing of psychiatric illnesses, and it's been recognised as a disorder since 1980. It is not, however, a very popular diagnosis yet. There are only 60,000 Google hits for it, as opposed to 1,600,000 for "major depression" and, er, 90,000 for "neuroskeptic". Odd for a disorder apparently plaguing at least 10% of women.

Indeed, some people say that it's no more than a label invented by psychiatrists who didn't understand women and then promoted by drug companies in order to sell drugs. This is almost certainly true, but it's also a bit simplistic, because there are people who perceive themselves as suffering from low libido, and if flibanserin really helps them, that's surely a good thing.

How is flibanserin supposed to work? According to a paper on the Pharmacology of Flibanserin, it's a serotonin receptor 5HT1A agonist and a 5HT2A antagonist. This makes it a kind of cross between the antidepressants nefazadone and buspirone. Neither of these are widely used as antidepressants because they're not considered highly effective. Flibanserin is also a weak dopamine D4 receptor partial agonist. This might underlie its aphrodisiac properties, because drugs which increase dopamine levels are known to enhance motivation and libido (or indeed cause problematic hypersexuality.) In rats and mice, flibanserin has sedative effects and enhances the effects of other sedatives. It also has antidepressant-like effects in some tests but not all. Drug geeks can click the image on the left for more details.

Now for the big question - does it actually work? Well, there have been no published clinical trials yet. At all. The trials in depression, where it failed to work, have never been published. Hmm. However, four trials in "Hypoactive Sexual Desire Disorder" were recently completed and the results were presented yesterday at a sexual medicine conference in Europe (ESSM) in the form of three posters (1,2,3). The trials were known as - groan - VIOLET, ORCHID, DAISY and DAHLIA. I probably don't have to tell you that they were all funded by Boehringer Pharmaceuticals.

The main poster is Efficacy of flibanserin 100 mg qhs as a potential treatment for Hypoactive Sexual Desire Disorder in premenopausal women which pools the data from three trials with a total of about 1,400 women. They found that taking flibanserin 100 mg every night had small beneficial effects. Relative to placebo, it increased the number of "satisfying sexual encounters" by 0.7 per month. It also improved scores on questionnaire measures of sexual function, a bit.

In any trial like this you have to ask whether there is result cherry-picking going on. Maybe they asked dozens of questions about the women's sex lives, and they're only telling us about the minority where the drug seemed to work? People often do that but in this case, the Clinical Trials Register suggests there was no funny business of that kind. It also shows that there have been no trials using 100mg which weren't included in the poster, so the trials themselves weren't cherry picked either. That's reassuring. But it looks like the effects were only significant when all three trials were pooled - one poster shows the results of the ORCHID trial alone, and most were non-significant.



What about the side effects? There's a whole poster about them. 100 mg flibanserin nightly caused 14% of patients to drop out due to side effects, vs 7% in the placebo group - so an extra 7% decided it wasn't worth it. It caused dizziness, nausea, fatigue, somnolence - and bizarrely, also insomnia. Notably, 50mg daily was much worse than 100 mg nightly, which suggests that taking this at night, rather than in the morning, is a good idea. But given what it is meant to treat, you'd want to do that anyway, right?

But this leads onto my biggest problem with these findings. It's obvious from the side effects data that this drug is a sedative - it makes you tired and sleepy. The animal data confirm this. It's much more likely to put you to sleep than it is to make you enjoy sex in any given month. Off the top of my head, I suspect its sedative properties are a result of its 5HT2A antagonism.

Any sedative can increase sexual desire, as anyone who has ever been to a bar will know. So whether this drug actually has an aphrodisiac effect, as opposed to just being a sleeping pill, is anyone's guess. To find out, you'd need to compare it to a sleeping pill, say, Valium. Or a couple of glasses of wine. Until someone does that, we don't know if this drug is destined to be the next big thing or a big disappointment.

Edit: Just noticed that Dr Petra Boynton has a fantastic post about the background to flibanserin and the manufacturer's apparent attempt to recruit her to write about HSDD.

[BPSDB]



Borsini F, Evans K, Jason K, Rohde F, Alexander B, Pollentier S (2002). Pharmacology of flibanserin. CNS drug reviews, 8 (2), 117-42 PMID: 12177684