If your pupils are tiny does it mean your on drugs?

Not necessarily. If you are in very bright lighting, your pupils will constrict to limit the amount of light allowed to enter your eye. This protects the retina from damage. Likewise, in very low light levels, your pupils will dilate (enlarge) in order to allow more light into the eye and improve vision. This is a normal process. However, there are a number of drugs that will cause the pupils to constrict, even to the point where they have a "pin-point" appearance. Opioid drugs (drugs derived from the poppy plant) such as opium, heroin, etc., will cause this pupillary constriction to the point of looking pin-point, even if exposed to low lighting levels. If a person is in normal lighting and has pin-point pupils, there is most likely something effecting this abnormal change.