For example:-

Eligibility Criteria For Drug Inspector In Maharashra:-

Age restriction : Bet 18 to 45 years.

Qualification :

Eligible applicants applying for the position of Drug Inspector should have degree in Pharmacy or pharmaceutical chemistry or in medicine with specification in clinical pharmaceutical or micro-biology from a university established in India by Law and experience after acquiring above qualification in the manufacture of testing of drugs or enforcement of the provisions of the act for a minimum period of five years.

If you satisfy eligibility conditions then you can appear for Drug Inspector job exam which consists of two papers.
One paper test knowledge of pharmacy subjects and drugs testing, and other paper consisting of general awareness and aptitude questions.

Hope this helps :)
Best of luck!