[fsk]

Maybe. There were several I tried that were horrible and only one I liked.

Most drug trials are 30-90 days. I haven't seen a study that tracked drug vs. placebo over years/decades.

In only 30-90 days, drug withdrawal can cause placebos to seem worse, if a patient switches from drug to placebo during the experiment.

[bmj]

Most drug trials are 30-90 days.

Is this specific to psychiatric drugs? I write software for a company that facilitates patient report outcome/clinical outcome assessment trials for the pharmaceutical industry, and we have trials that run for years. I don't believe our products have been used in a psychiatric drug trial, though.

[fsk]

For any drug trial, if a patient switches from drug X to placebo, compared to patients who switch from drug X to drug Y, that could cause the placebo to seem worse than it actually is, due to withdrawal.

All the drug research I read regarding psychiatric drugs had a 3-6 month timeframe max.

Another flaw is that "Is the patient doing well?" was based on the subjective opinion of the doctor. (Even if the doctor does not know which patients are taking placebo, a competent psychiatrist should be able to tell. "Compliance with medication" is one thing doctors are trained to look for.) I would have liked to see other objective metrics, such as "How high can the patient score at Tetris?"

A multiyear psychiatric study is very hard, because many patients will struggle to follow any treatment plan. Also, placebos might cause the patient to initially get worse before they get better, whereas a drug might cover up symptoms while hurting long-term recovery. It's hard to find patients who would follow through for years.