What Drugs Cause Dilated Pupils?

Pupil size can indicate drug use. Understanding which substances cause dilated pupils helps identify potential substance abuse in loved ones.

Stimulants like cocaine, amphetamines, and MDMA cause significant pupil dilation. The sympathetic nervous system activation from these drugs triggers this response.

Hallucinogens including LSD, psilocybin mushrooms, and DMT also cause pronounced pupil dilation as part of their effects on the brain.

Some prescription medications cause dilated pupils, including certain antidepressants, antihistamines, and medications for Parkinson's disease.

Conversely, opioids typically cause constricted (pinpoint) pupils. This is a hallmark sign of opioid intoxication and can help distinguish opioid use from other substances.

If you notice dilated pupils along with other signs of drug use in someone you care about, addressing the issue with compassion is important. Treatment is available and effective.