Many pharmaceuticals have weight gain as a well-documented side effect. The weight gain can be due to a variety of factors, including, but not limited to, lowering metabolic rates, causing hyperinsulimia (especially in anticonvulsants like neurontin and depakote), and many other biochemical effects that are not easy to put into layman's terms. To put it simply, these drugs work because they have a specific chemical effect, but they often react with other biochemical processes in ways that are either not anticipated, or are considered to be less important than the intended therapeutic effect.
To put it simply, a living animal is not a laboratory calorimeter, where calories in and calories out are a simple function. We are infinitely complex, and adding a molecule to the living system can help some problems, but modern medical science is not yet fine-tuned enough to successfully target one tiny process. Our SSRIs and other antidepressants are often like taking a blunderbuss to a rifle range--you will probably hit the target, but you'll hit a lot of other stuff too.
That's what progress is all about, though. A hundred years ago, you probably would have died if you had an acute gallbladder, while today a doctor plucks the quivering organ from our innards with a watchmaker's precision, making a cholecystectomy a very simple and survivable surgery, with smaller and smaller scars as tools and techniques sharpen. When I was a teen, I waited anxiously at a hospital in Milwaukee, five hours from home, for my grandfather's quadruple bypass to be completed. Today, he probably would have had stents neatly slipped into his blocked arteries, with only a pinprick on the surface of his skin to show for it.
Before we had antidepressants and other mental health drugs, we had some of the most inexcusably abusive quackery inflicted upon the mentally ill. Historically, mentally ill people were often just dumped in prisons and jails (and guess what--we're still doing it; ask any social worker). Some were treated to cruel, sometimes deadly exorcisms. Women were presumed "hysterical" and went to doctors for vaginal "massage" to induce orgasm as a treatment. Lobotomies became all the rage in the late 1940s, with frontal lobes scrambled with an ice pick through the eye socket. Asylums were often notorious for their squalid, cruel conditions, with many exposed by family members who were horrified at their relatives' treatment.
In the 1950s, the advent of psychotropic drugs was the first ray of hope for mentally ill people. I feel that we're finally seeing the tail end of the birthing pains of psychopharmaceuticals, with more solid research and standards being applied. The system is obviously not yet perfect, but important lessons have been learned, with our ancestors' brave--albeit not always informed--foray into citizenry as research subjects.
So, today, instead of a schizophrenic being shackled into a cold cell, at the mercy of potentially abusive captors, that person may be able to function normally with the help of a drug such as Risperdal. They may be able to work, have a family, and enjoy their lives. If the drug that enables them to function also causes them to gain weight, I question those who wring their hands over the weight gain. Surely the fact that they can live their lives independently is a pretty good trade-off for the potential stigma associated with the weight gain? And, if it is indeed the stigma the hand-wringers are concerned about, what is preventing them from working toward a better world, one where a fat person is not subjected to social stigma? Is their aesthetic sense so deeply rooted that they can't stand to see a happy person who happens to have a body shape that is not attractive to them?
Some of the best-selling drugs today are antidepressants, especially the SSRIs. They have helped millions of people become reacquainted with life, to poke their heads out of the steep-walled pit that is depression. Anxiety, another condition treated by SSRI, can be so disabling that its sufferers sometimes cannot even leave their homes. I think it is absolutely ridiculous that anyone would be so upset over the associated weight gain, when the drugs often make a person feel as if his or her life is worth living again. I'm tired of hearing the fatophobes shrieking about it, trying their damnedest to drag down those who have finally been able to stand up again, just because their bodies are different.
So tell me, fat-haters, are you really so shallow and juvenile that you would rather see someone institutionalized than fat? Hanging themselves instead of fat? I've really begun to wonder if the fat-hate is not just about fat, but about an excuse to be misanthropic to anyone who is socially vulnerable. After all, the mentally ill you used as a punching bag in ages past have now become functional fat people, so whom are you going to punch in their place? My suggestion to you is to find out why you need a punching bag at all, and then fix it, rather than continuing to delude yourself into thinking your victims deserve your abuse. Maybe you could even try one of the above drugs--it might even be good for you to see what it's like to gain weight without changing your eating or exercise habits.