Branded vs generic Parkinson's drugs

Most Parkinson’s drugs can have two names – a generic name and a brand name. But is there a difference between them? We find out. 

What are branded drugs?

A pharmaceutical company that owns a particular drug will create the drug’s brand name. Two well known brand names for the Parkinson’s drug levodopa are Sinemet (made by Merck Sharp and Dohme Limited), and Madopar
(made by Roche Products Limited).

If a company has a patent on a particular drug, then they are the only ones who can market it under that name once the drug has been granted a license.

What are generic drugs?

Once a patent has expired, other pharmaceutical companies are allowed to manufacture the same medication under its generic name.

The generic version of the drug will be the same as the branded one because it contains the same active ingredient and is used at the same dose. Roche’s Madopar, for example, is available on the market under the generic name co-beneldopa. But only Roche is licensed to sell it as Madopar.

Generic drugs are checked to ensure they work the same and have the same standards of quality and safety as the branded version.

The NHS will often use the generic drug because they are as effective as the branded version, but cost less. They are generally cheaper because the costs come from developing and marketing a new drug.

So, is there a difference?

Branded and generic drugs contain the same active ingredient. Sometimes, the non-active ingredients (known as ‘excipients’) may be different from the ones used in branded medication. These include sugar, flavouring and colouring.

This means a generic drug might look or feel different in terms of shape, colour, size and texture, from its branded equivalent. These differences won’t have any effect on the way the medication works in your body – the two are still the same because the active ingredient is what gives a medicine its therapeutic effect.

However, the speed at which tablets or capsules dissolve and are absorbed into the bloodstream can sometimes be different between different brands. Occasionally, this will have an impact on the level of the medication in the body.

Spilt tablets

This is known as a ‘narrow therapeutic index’. It means that there isn’t much difference between the level where the medicine has the intended effect, and the level being either too high (causing side effects or being toxic) or too low (being ineffective).

The therapeutic index of some medications can change as your Parkinson’s progresses. Doses can become less effective, or have more side effects. This can happen with generic and branded medications.

So because of these reasons, you may find that a particular medication suits you better than the other.

What do I do if I'm worried I haven't got the right medication?

The best thing to do is to always pay attention to the label and packaging on your medication if the tablet or capsule looks different.

If you prefer to take a particular brand of medication, ask your GP to write the brand name on your prescription and then you will always receive that brand from your pharmacist.

If you notice any changes in your symptoms after swapping to a different brand, you’re ever unsure about the name of your medicine or you have questions about your prescription, talk to your GP, Parkinson’s nurse or pharmacist.

  • Thank you to Dr Janine Barnes, Neurology Specialist Pharmacist and Vicky Travers, Clinical Nurse Specialist for helping us put this article together.

Find out more about Parkinson's drugs.