That is not what I meant, but it can work that way. The example I gave explained what I meant. My friend was on one medication that was working fine for her, but when she lost her insurance, she could no longer afford that medication, so the change was "forced" upon her by economic considerations.

There are times when a doctor may feel that a medication change is in the best interest of the patient, and may insist upon the change. Here in the U.S., a patient has the right to refuse treatment, so that patient could refuse the change. But a doctor also has the right to refuse to treat a patient (in a non-life-threatening situation), or to stop prescribing pain medications if s/he feels that is justified.

I do not know what the practice/policy is in other parts of the world.

She was still opioid tolerant, yes, but she is less tolerant of the MSER than she was to the Oxy. This is one reason rotation is done.

Once a person has become opioid tolerant, they remain tolerant until their bodies adjust to having less/no opioid present. This can occur slowly over a long time by slowly reducing the amount of opioid present, or suddenly, in which case they go through withdrawal.

When a doctor changes a patient's opioid medication, it is usually done by titration. They start with an intentionally low dose (often about 1/2 of the equivalent dose of the original opioid), and increase as needed until they find the lowest dose necessary to provide the desired effect. Some temporary withdrawal symptoms may occur, but not nearly as severe as if the patient stopped abruptly.

Even more care must be taken when rotation/switching to methadone - titrating more slowly - because of the potential for adverse reactions. This has been discussed on other threads re: methadone.

Doc