{"id":19824,"date":"2021-10-28T07:33:25","date_gmt":"2021-10-28T07:33:25","guid":{"rendered":"https:\/\/www.optometrists.org\/?page_id=19824"},"modified":"2021-10-28T07:33:25","modified_gmt":"2021-10-28T07:33:25","slug":"why-is-my-pupil-small","status":"publish","type":"page","link":"https:\/\/www.optometrists.org\/general-practice-optometry\/guide-to-eye-health\/conditions-that-affect-the-pupil\/why-is-my-pupil-small\/","title":{"rendered":"Why Is My Pupil Small?"},"content":{"rendered":"

Normal pupils are usually 4-6 mm in diameter in room lighting. With miosis, the pupils are less than 2mm.<\/b><\/h2>\n

Your pupil is the dark circle in the center of your eye. It grows and shrinks thousands of times per day. It enlarges to let in more light while you’re in dim light and shrinks to protect your eye and keep light out while you’re in bright light.<\/p>\n

What is miosis?<\/b><\/h2>\n

Miosis is a condition where your pupil shrinks or constricts in size.\u00a0<\/b><\/p>\n

If your pupils remain small even in dim light, it could indicate that something in your eye isn’t operating properly. This condition is known as abnormal miosis, and it can affect one or both eyes.<\/p>\n

There are many causes of pupils shrinking in size:<\/p>\n

Age<\/b><\/h2>\n

It’s usual for a newborn’s pupils<\/a> to remain small for roughly two weeks so that their eyes are shielded from strong light.<\/p>\n

In old age, the pupils begin to shrink as well. The muscles that control the pupils can become weak, making it difficult to open them. It may be more difficult to see at night as a result.<\/p>\n

Inflammation<\/b><\/h2>\n

Swelling inside the eye can make it difficult for the pupils to expand.<\/p>\n

This can occur due to an eye injury or could also be due to a condition known as uveitis<\/a>, which causes swelling in the iris and the tissues around it.<\/p>\n

Medication and narcotics<\/b><\/h2>\n

Miosis can also be caused by medication side effects.<\/p>\n

Certain medications for anxiety, muscle spasms and seizures, such as diazepam (Valium) and antihistamines like diphenhydramine (Benadryl), can cause the pupils to shrink.<\/p>\n

Narcotics, whether prescribed or illicit, can do the same.<\/p>\n

Some of the commonly used drugs that can cause miosis are these opioids;<\/p>\n