Shouldn't affect you too bad, but I think you still have to list it because it's an "institutional action". They might ask you about it during your interviews, but honestly I think it works to your advantage being able to explain the situation.
It might affect you. You said stress was the factor? Well, medical training is stressful and something adcoms look for is the ability to handle stress.
It could be a potential red flag but don't prematurely freak out. Make sure you can explain it well and that you have addressed the problem. If it is on your record, you WILL have to put it down and you WILL have to explain it on the app and in interviews. So be ready.
Below is my response to the AMCAS institutional action question. Is it good enough? did i go into too much detail? not enough? I greatly appreciate any feedback. Someone in another thread helpfully pointed out that i should make it as vague as possible...any other ideas?
Due to stress and a relationship issue at the beginning of junior year, I wrote a few concerning remarks about a student on my Facebook page. No inappropriate/unlawful interactions between us ever took place, but as both a precaution and a way to help me properly handle my stress, a dean prohibited further contact with the student and instructed me to seek continual and active counseling violation of either would result in institutional action. At the end of junior year, I missed a counseling appointment and didnt reschedule. Consequently, I was found responsible for failure to comply with a university directive and given a disciplinary warning.
I took full responsibilities for my mistake, and I began to interact more proactively and regularly with my therapist. As a result, I learned how to effectively manage my stress and improved my overall physical and emotional wellness. I became more productive, efficient, optimistic, and one step closer to medical school.