This can account for the ways in which your emotions or mental state may affect pupil size. Pupil size can also be affected by the neurotransmitters or certain chemicals in the brain. The retina senses light and converts it into neural signals, which allow for visual recognition-that is, the ability to see.

In dim light, for instance, your pupils may expand in order to allow more light to reach a thin layer of tissue known as the retina. Pupil size generally changes according to factors such as light, distance, and colors. If you suspect that someone you know is abusing drugs, it may be helpful to know how some drugs may change pupil size. Pupils can change in size due to a whole host of factors, including mental and emotional state, certain health conditions, and brain injury.Įven so, changes in pupil size are also one telltale sign to indicate that a person may be intoxicated or high. rapid, uncontrollable movements of the eyesĬhanges in pupil size are not necessarily indicative of drug use.Some can also affect eye motion, cause watery eyes, and cause redness of the eyes-a well-known sign of marijuana use.Įye changes that can indicate drug use include: Drugs can affect pupil size in different ways, depending on the type of drug. Pupils are the black dots that rest in the center of your eyes.

Some of the most obvious ways to detect the use of drugs like hallucinogens, marijuana, or stimulants are physical side effects-including changes in pupil size. Long-term substance abuse may also increase your risk for certain eye conditions, including glaucoma and vision damage.ĭrug use can be detected in a variety of ways. Some drugs, such as opioids and stimulants, can enlarge or reduce the size of your pupils. Substance Abuse Among Indigenous Populations.

Eye pupil size meaning