Rare

The matrix patches are just as effective as the reservoir (gel) patches. They work extremely well and are very easy to live with because they are completely flat with no risk of loss of the drug from the patch by puncturing etc. I appreciate they may not look like much but I can assure you they are highly effective.

However, the two types are not interchangeable. If you are using reservoir patches then you should be continuing with them and shouldn't suddenly be prescribed the other type because the dosing isn't quite the same. In theory there should be no difference in the effectiveness of different manufacturers' patches provided they are both reservoir or both matrix types. In reality, some people find that they will get on better with one particular manufacturer's patches.

If you are being deliberately swapped from one type to the other then your prescriber should be discussing that with you and making allowances for any dosing difference but it sounds as though this has change happened to you by accident. I think you should check the situation with your prescriber and take advice before doing anything else.

The matrix patches are extremely difficult to abuse so it would seem likely that their use will increase. The reservoir type can be cut open and the whole contents eaten by drug abusers to provide a 'hit'. This is impossible with the matrix patches - they will only deliver at the stated rate so they are of little interest to abusers.