At their basic level, all drugs comprise of chemicals in a certain proportion. Branded drugs are drugs for which pharma manufacturers have obtained the approval of the concerned medical authority of their respective country.
A drug contains active as well as inactive ingredients. It is the active ingredients that determine the efficacy of any drug. Patented drugs have a particular formula which the company manufacturing it has deemed as ideal.

Generic Drugs

A generic drug is a drug that contains the same active ingredients as a branded drug. Most countries have laws which protect branded drugs for a certain time. This period can vary from 7 years to 20 years. After expiry of this period, anyone can produce the drug by using a different brand name. Sometimes, a generic drug may retain the patent on the formulation but not the active ingredient. In other words, generic drugs are identical or bioequivalent of the branded drugs as far as their pharmacokinetic and pharmacodynamic properties go. They have the same efficacy and use as the branded drugs.

Approval Process for Generic Drugs

Generic drug manufacturers are not required to repeat the extensive clinical trials used in the development of the original, brand-name drug. Instead, they must show they are bioequivalent to the pioneer drug and fall into acceptable parameters for bioavailability, or the extent and rate at which the body absorbs the drug.
Scientists measure the time it takes a generic drug to reach the bloodstream. This gives them the rate of absorption or bioavailability of the generic drug, which they then compare to that of the pioneer drug. The generic version must deliver the same amount of active ingredients into a patient's bloodstream and in the same time as the pioneer drug. Brand-name drugs are subject to the same bioequivalency tests as generics when their manufacturers reformulate them.

Conclusion

Both brands and generics are of the same quality, as their facilities have to meet thesame strict productions standards of Good Manufacturing Practice (GMP). But generic drugs save patients substantial costs without compromising on their quality. As an example, paracetomol, an active ingredient in many patented drugs, is sold as a generic drug for a very low cost – as low as 2 cents in some countries. Thus, because of their low price, generic drugs are often the only recourse the poor can access.