1. you haven't mentioned about the cause of emotional upset or stress
, is that was due to some relationship problem,parental problem, financial crisis,any sad news, examination pressure,any anxiety
or panic disorder, due to use of some medications, or perhaps due to Over exhaustion???
2. any cardiovascular abnormality detected by the Health Physician?
3. although medication was given to control his blood pressure (as said by you) but it is not clear,whether it was given for high BP
or Low (please mention the BP reading of that time)
4. Stress will not cause coma unless related with any Systematic disease, (hypertension
, Renal) but can cause Catatonia, consult with your doctor for any further investigations like ECG, USG of Kidney
5. take diet rich in Vitamin D and Vitamin B complex along with omega 3 fatty acids (DHA,EPA)
6. Avoid the Emotional trigger (if possible)
7. take anti oxidants like Walnut, Almonds, Pistachios which also work as Immunomodulators (on Immune System ).
8. calcium in milk and other sources helps in reducing muscle spasms and reduce emotional tension.
9. to achieve a healthy life style, not just medicine but he has to focus on his emotional component also,yoga and meditation
will help in attaining the positive attitude,and keep remaining calm and stress free.