Friday, February 22, 2008

Wellbutrin (bupropion)

Ron Rosenbaum has a post on the baseball steroid issue. A commenter talked about how Wellbutrin helped him but not so much the generic; which leads to some thoughts on Wellbutrin (bupropion). In the late eighties, a patient and I were considering his using Wellbutrin. "Is it a new drug?" he said. "Yes," I replied. "It must be better then," he said. Some truth to that. Another favorite patient story is about Wellbutrin. An older, wiry black man came for an appointment at the VA. "Doc, I usually don't take your medicine, but when I do it sure does make me feel peppy!" Some medications have deficiencies that, addressed, are useful to the manufacturer because they allow for a new formulation that works in the marketplace (and have patent exclusivity); such is the case here. Because of a slight increase in seizure risk, the drug is supposed to be taken multiples times a day at intervals; I hope God has better luck with his rule on adultery because these intervals and maximum individual doses were never followed by anyone coming to me on the drug, not that it seemed to matter. I have a patient who, when I was going to renew the drug as the SR (sustained release) told me to give him the IR, the immediate release or just the original formulation. The IR was available in generic but the patient wasn't concerned with price. Subsequently I was at a lecture sponsored by a rival, Forrest, and the presenter said that the registration trials for the SR and XL were not positive, in other words the drugs didn't 'work' but the FDA gave them licenses since the original Wellbutrin was allowed. These statements were consistent with my patient's claim. It is also likely that the brand name manufacturers original SR and XL products come closer to being likely effective than the subsequent generics which only have to demonstrate delivering within 20% of the branded product over a certain interval. In practice this usually means you get 80% of the amount of drug. So I would wonder if the commenter could do well on generic original Wellbutrin or the IR bupropion taken (more or less) under the original rules. Wellbutrin is a useful drug on the psychiatry consultation service. It helps older people who may be grieving over the loss of loved ones or their own health. There it may work at 150 mg a day and one needn't go to the usual 300 mg a day. Low Na+ from the SRIs in older people is often seen in psychiatry consultation and Wellbutrin does not have this side effect. It shouldn't however be used where there is end stage renal disease because the metabolism of the drug is prolonged.

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