Leading pharma companies including GlaxoSmithkline, Pfizer and Ranbaxy sell commonly used drugs at a rate 10 times the cost of production, a study by the Corporate Affairs Ministry has found.

A study by the Cost Audit branch of the MCA found drugs like Calpol manufactured by Glaxosmithkline, Corex Cough Syrup by Pfizer, Revital by Ranbaxy Global, Omez by Dr Reddy's Labs, Azithral by Alembic and several others were being sold at a mark up of up to 1,123 per cent over the cost of production.