I’ve received several complaints from patients and readers about one of the current buprenorphine formulations. The primary complaint is that the tablet is ‘not ‘working as well as the other formulations;’ that it seems to wear off earlier, or that people feel compelled to take more than what is prescribed.
My understanding, admittedly based only on what people have told me, is that there are three current formulations of buprenorphine. The brand form, Subutex, comes as a relatively-large, flat-oval tablet, white or off-white in color. The Roxanne version is a round white tablet, with a diameter of about 0.5 inch. The tablet people have complained about is from Teva, and is smaller; about the size of a tic-tac.
In general, I think that generics are as good as brand name medications. I have never come across a reliable instance, in my practice, of generics being less potent or less active. I recognize that particularly for psychiatric medications, the placebo effect accounts for significant portions of the actions of medications—so if a person BELIEVES that generic fluoxetine is less likely to work, it IS less likely to work. But take away the placebo issue, and a molecule of fluoxetine is a molecule of fluoxetine—regardless of where it comes from.
That said, I realize that the delivery of molecules can be affected by the design of capsules and tablets. I remember a study, years ago, that showed that many of the vitamins sold in the US passed through the intestinal system without even dissolving, let alone getting into the bloodstream. If the active substance is encased inside insoluble resin, there is little to be gained from taking it.
The delivery issue is less of a concern with a medication that is delivered through the oral mucosa, as with buprenorphine. There are several factors that affect absorption of buprenorphine; the concentration of buprenorphine in saliva, the amount of surface area that buprenorphine is allowed to pass through, and the time allowed for that passage to occur. If the smaller tablet dissolves more slowly, molecules of buprenorphine may have less actual contact-time with oral mucosa, thereby reducing absorption.
On the other hand, I am well aware of the psychological reward that people describe from taking buprenorphine or buprenorphine-naloxone, even in the absence of any subjective sensation. The fear of withdrawal is relieved by taking buprenorphine—making the dosing experience ‘rewarding.’ It may be that the smaller tablet provides less reward, as the small size engenders less confidence in those unfelt ‘effects.’
In any case, I invite readers to share their experiences, just in case those who have already written are truly onto something. Please leave comments below—and thanks for sharing!