Before giving a patient a first prescription for a drug, the doctor should explain several points. He should make clear what effects are likely to be experienced on first taking the drug, e.g. drowsiness or dry mouth. He should also explain how long it will be before therapeutic effects appear and what the first signs are likely to be, e.g. improved sleep after starting a tricyclic antidepressant. He should name any serious effects that must be reported by the patient, such as, coarse tremor after taking lithium.
Finally, he should indicate how long the patient need to take the drug. For some drug such as anxiolytics, the latter information is goven to discourage the patient from taking them for too long; for others, such as antidepressants, it is given to deter the patient from stopping too soon.