I gave them something dangerous during the trial and they didn't agree to a follow up. I discovered they need treatment now or they will die (may happen with a poisoning for example). I am still contacting them and I surely hope you would too.
1) If the contract signed by the patient is silent on the topic, and you have their information, you are free to contact them.
2) If the contract signed by the patient explicitly says you can not contact them for this reason, then I think it clearly unethical to do so.
3) If the contract is ambiguous, or the intent is unclear, then it is a judgement call.
I am talking about #2 and I think you are talking about #1 & 3.
There are valid reasons why people would want to select #2, and if they do, their wishes should be respected.
>Another example: a study for rare condition was conducted. No effective treatment was found. A few years later very promising treatment was discovered. Wouldn't you like to know, even if the original form didn't ask your permission?
You are literally describing healthcare providers giving confidential medical information to third parties without consent. In no way should anyone but the patient be able to void or reinterpret the contract, their presumption of the patients wishes should never override those stated by the patient.