DIFFERENCE BETWEEN BRAND AND GENERIC DRUGS
Is there a difference between generic and brand name medications? Yes. And it's more than cost.
On paper there's no apparent difference between say, 100mg of Viagra (brand) and 100mg of Sildenafil (generic), but in practice there often is a world of difference between the pharmacokinetics (how fast it takes action, how long it lasts, its side effect rates etc) of generic and brand name medications, and even from one generic to another. What is this madness?
Consider another example: methylphenidate (generic name) versus Concerta (brand name) for ADHD treatment. Both use the same chemical methylphenidate base as their active ingredient. But in clinical practice, many patients mine included, have been quite irate by the switch vetted by their insurance payors. They report that the generic sucks. It doesn't have the umph they're used to and doesn't last through the day. When complaints first started making their way back to me a few years ago, I at first being a typical paternalistic doc thought it was some kind of mass hysteria amongst my patients. But similar feedback again and again boomeranged back to me for many other ersatz knock-offs too. Since then humility has overtaken my cock-sureness and I've become a believer that the differences are real. The problem boils down to generics use their own blends of cheaper - read inferior - binders and fillers to wrap around the active drug. Cutting these corners makes their products a low cost alternative. But qualify concomitantly suffers.
Generics ay not deliver the active drug at the same rate as the brand does, they may disintegrate prematurely in the gut, they might bind the dosage too tightly, and a host of other inefficiency issues. It's like buying a knock off designer handbag from a street vendor. It may look the same, but an expert can show you the poor stitching built into the lower cost. In the case of Concerta, the difference in effectiveness came down to a sophisticated slow release system in the brand version, with a poor replication in the generics.
Generic manufacturers also get a free ride through the regulatory process as they do not have to demonstrate the safety of their products with the scrutiny that original patent holders do further reducing their production cost - but also their reliability. So I've also seen side effect in some patients on generics that do not fit with what I expect from the brand version. When it comes to prescription drugs, like most everything else in life, you do get what you pay for. But because the margin in cost can be so wide, I still try generics at least once in my patients; if it works nearly as well as the brand competitor, you can still stand to save some real paper using generics.