manifest. 1  readily perceived by the eye or the understanding; evident; obvious; apparent; plain: a manifest error. 2  Psychoanalysis. of or relating to conscious feelings, ideas, and impulses that contain repressed psychic material: the manifest content of a dream as opposed to the latent content that it conceals.
In medicine, an adverse effect is an undesired harmful effect resulting from a medication or other intervention such as surgery. An adverse effect may be termed a  side effect , when judged to be secondary to a main or therapeutic effect.
Cumulative Effect of Drugs. 1. Due to too frequent doses. 2. Due to too long continued administration. By cumulative effect is meant the unexpected, intense action of a drug after it has been given for some time, as differing from an immediate intense action of a drug which would show an idiosyncrasy.1.. Cumulative Action From Too Long Continued Administration of a Drug means the development of symptom a which show an over-action of the drug. This is of frequent occurrence and is sometimes accidental, but is often caused deliberately by pushing a drug to its full physiologic effect.