I currently work QA/QC in pharmaceuticals. I work under a generic brand company as part of a sister company.

While the ingredients are required to be exactly the same, there are some issues that generic brands run into a lot more. And it seems to all lie in quality control. With name brands, they put a lot into their QC/QA systems because they have a reputation and a name to protect. Name brand pharmaceutical companies also have a lot more money to work with. With generic brands, cost is a huge factor since they sell drugs for cheaper and are working against big pharma companies, so many generic brands move their factories into locations to save financially. Downside is the factories are located in a geographical area where they just don't seem to meet European and FDA standards. As a result, bad batches occur more often. Without a sound quality control team who have an understanding of the pharmaceutical regulations, bad batches get to the consumer. If lucky, the company will be able to throw out advisory notices and recalls before the drug makes it to the consumer, but many times, by the time head office gets word of a bad batch, the field reports and complaints are already coming in.

Now, I am not telling anyone to buy name brand over generic. Hell, even I buy generic medications. In terms of making the choice between buying generic versus name brand, as much as cost is a deciding factor, I recommend people look into recalls or errors made with the particular drug they require. For example, with contraceptive pills, I will only buy the name brand. The reason is because the generic version of the contraceptive I take has been recalled several times due to big mistakes. I really don't want to take the chance of buying one of their mistakes. So for very important medications (such as heart or blood pressure medication) look into reports before you buy. If there is a lot of recalls over the years with a particular drug, it's a good indication their quality control system is not doing their job properly.

Just a few notes as well. Generic brands have their own facilities. While some may manufacture in the same facilities as big pharma companies do, many don't (big pharma companies do not like generic brand companies very much). Also, if the drug you require was manufactured in a plant in India, I highly recommend not buying it. The number of screw ups I've seen from drug manufacturing plants there is a little alarming....especially since in some cases the workers were altering the results so the drug could pass acceptance criteria. And that type of mess up is really really really bad.