It also means that the heroin has affected the control of involuntary actions, such as the beating of your heart. When the heroin pupils constrict, it means the heroin has affected the automatic nervous system that controls bodily functions when a person is at rest. The constriction that happens to heroin users occurs when the heroin attaches to the opioid receptors in the brain and changes the central nervous system. The fact is, most other substances cause the pupils to enlarge, or dilate. Other abused drugs can affect the eyes, but heroin and other opioids are common in bringing about the constriction of the pupils. Along with the unique pupil size, their eyes will often be bloodshot and maybe a little droopy. Why Do Opioids Constrict Your Pupils?Īn individual that suffers from heroin addiction will display constricted, even pinpoint pupils. Therefore, using the following drugs can cause dilated pupils or constricted pupils as a side effect. Neurotransmitters play a part in the size of your pupils. Many drugs impede your brain’s chemical messengers, known as neurotransmitters.

Why Do Drugs Affect Your Pupils?ĭrugs affect the muscles that enlarge or shrink your pupils. You can’t control it, even if you want to. Pupil dilation is an involuntary nervous system response, whether it’s caused by internal or external factors. – Mydriasis (enlarged pupils in bright environments) – Congenital aniridia (a deficiency in the PAX6 gene)

Health conditions such as: – Holmes-Adie syndrome (a neurological disorder).

Internal factors that affect dilation include: That’s because your pupils are affected by internal factors too. You’ve probably heard that looking at someone you love can make your eyes dilate.

Color and distance are other external factors that affect pupil dilation. This makes it possible for more light to reach the retina, which makes it easier to see.

Changes in the eye, such as motion, pupil size, and the color of the whites of the eyes can help to determine whether a person is intoxicated and what substance they used. Drugs and Pupil DilationĪlcohol and drug abuse cause side effects like nausea, drowsiness, and loss of coordination but they also have an effect on your eyes. Opioids act just like opiates in the body because of their similar molecules. Thus, all opiates are opioids but not all opioids are opiates. Technically, “opiates” refer to just the opioids that are “natural” or made directly from the poppy plant, while “opioids” refer to all the opioids, including the ones that are natural, synthetic, or semi-synthetic. Opiate pupils are “pinpoint pupils” that don’t respond to changes in lighting. Opioids and opiates cause your pupils to constrict, or get smaller (miosis). However, other factors, such as drugs, can also affect the size of your pupils. Depending on the lighting conditions, your eyes can grow or shrink. The dark part of your eye is called the pupil.

Pinpoint pupils meaning drugs