Prozac (fluoxetine) does not seem to be effective, in general, in helping in recovery from anorexia nervosa. However, continuing research seeks to determine whether fluoxetine can be helpul in preventing relapse in anorexia once a person has achieved normal weight gain in recovery.
Background: Fluoxetine and Anorexia
Prozac is a brand name for the drug fluoxetine hydrochloride. It is commonly prescribed as an antidepressant. Fluoxetine is a selective serotonin reuptake inhibitor (SSRI), meaning that its effect is to keep the brain from reabsorbing serotonin once it is secreted. Serotonin can have a positive effect on mood. So preventing it from being reabsorbed keeps it active in the brain for a longer time, with the intended effect of normalizing a depressed mood.
Because those with anorexia often experience depression, it has been natural to suggest that fluoxetine could be of help. Depression makes recovery from any other mental or physical condition harder. Also, fluoxetine has been known to improve symptoms of obsessive-compulsive disorder (OCD), which is common in those with anorexia.
Another reason that fluoxetine is often prescribed for those with anorexia is that it is the only drug approved by the FDA for treatment of depression in children and adolescents between 7 to 17 years of age. There has not been a rush from drug companies to try to get their meds approved for this purpose.
Fluoxetine Considered Ineffective as a Primary Recovery Aid
Early research studies employing fluoxetine in anorexia treatment were promising, but small -- and they were not conducted using the most reliably accurate study methods (they weren't done using double-blind placebo-controlled trials). Still, the results warranted further pursuit, and larger studies followed.
Unfortunately, the more rigorous studies did not confirm the early results. Many suggest that fluoxetine does not help those with anorexia who remain underweight to achieve recovery. In fact, other research indicates that even with added nutritional supplements, fluoxetine is ineffective in helping underweight persons with anorexia to gain weight. Plus, they seem to experience no improvement in anxiety or OCD symptoms.
Why Fluoxetine May Not Help As a Primary Recovery Aid
The digestive systems of those with anorexia are often in bad shape from lack of use. The body actually "forgets" how to digest. This also applies to medications: The body has trouble metabolizing the drug, and thus it cannot get the drug's intended effect.
Some think that self-starvation creates a shortage of tryptophan, which is a building block of serotonin. For these reasons, one option to consider is increasing the dose of fluoxetine in an effort to force what little serotonin is available to stay unabsorbed and active as long as possible.
Further, in some relatively rare cases, fluoxetine can suppress appetite. Case studies exist in which those with bulimia nervosa or binge-eating disorder saw a reduction in their binging with fluoxetine, but then went on to restrict food intake. It is important to stress that this side effect is uncommon; fluoxetine normally does not impact body weight.
Conflicting Results For Fluoxetine For Prevention of Anorexia Relapse
Where fluoxetine has given more hope is in the prevention of relapse. The idea is that the drug can limit symptoms of depression and anxiety that bring on a desire to return to old eating disorder behaviors. Some research demonstrates that fluoxetine can do just that. But even this more hopeful finding has its skeptics, and they have their own studies to back them up -- suggesting that the drug is no better than a placebo in prevention of relapse. The usefulness of fluoxetine in this area is an open question in the research community.
What Do We Conclude About Fluoxetine and Anorexia?
As the only FDA-approved drug for childhood and adolescent depression, fluoxetine is unique and therefore useful. In the right situation, it may help improve symptoms of depression and anxiety for those who are underweight. However, the drug's effects in these cases are not as predictable or dramatic as they are for persons who are not underweight. Those who have achieved recovery may find it helpful in avoiding relapse. In all cases, a key step is to consult thoroughly with a doctor before taking it. It's helpful to ask about the most recent research, discuss the pros and cons of taking fluoxetine, and form reasonable expectations. And medical practitioners, of course, must remain up to date to ensure that they are offering their patients treatments that are most likely to make a difference.
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