I am designing a website on medicines and drugs. The site provides technical data to researchers/health professionls as well as non-technical information to patients and casual visitors. Kindly help me that how can I find information about which drugs (out of hundreds available in market) are the most searched ones and which can earnme more money with google ads. thanks in advance.
I would look at statistics for which medications are the most prescribed for a given ailment. I wouldn't recommend taking on the entire medical field and expect a whole lot of positive feedback. Maybe start with heart medications or something the like and expand from there once you have that working. Commercials commonly seen on TV are also a good indication that the medicine is being pushed hard or is already established in the market. You could probable even call you doctor and ask some questions regarding their particular facility. Nursing homes and pharmacies are a good places to ask too.
You can look up specific keywords to get the search volume at Yahoo here http://inventory.overture.com
I prefer using Google's Keyword Tool because it not only tells you search popularity for the keywords you enter, but also how much AdWords competition there is. If a keyword is searched for frequently and is highly competitive in AdWords, it will likely earn more money than one that has no competition and/or isn't searched for often.
Something like that would work well if you had a big list of medicines and could use that list to generate individual adgroups, (using something like speedppc). Really the only true way to find out which ones are best is to test them.