Patient groups and experts have voiced their concerns at the Department of Health's plans.
At the moment more than 80 per cent of prescriptions are written generically.
But the former director-general of the Association of the British Pharmaceutical Industry, Professor Trevor Jones, says many generic drugs can be slightly different from their branded counterparts and from each other
This could compromise the effectiveness and safety of medicines taken by thousands of people with health conditions including epilepsy, asthma, skin disease or who have had an organ transplant.
Generic medicines often have a different size, shape, colour and packaging from each other, and branded medicines.
To help decide whether it will proceed with the proposals the Department of Health recently issued a public consultation on the proposals open until 30 March.