Tag: Pupil constriction

First isolated in the 19th century, physostigmine was historically used in ophthalmology for its effects on the eye. To answer the question, 'Is physostigmine miotic or mydriatic?', one must examine its pharmacological role as an indirect cholinergic agonist that results in pupillary constriction.

Opioid-induced miosis, the characteristic pinpoint pupils, is one of the most sensitive and frequently assessed objective indices of opioid effects. This phenomenon is a direct result of how these powerful substances interact with specific brain receptors, triggering a cascade of neurological events that forcibly constrict the pupil.

Miotics are a class of medication specifically designed to constrict the pupil. A prominent example is pilocarpine, the primary drug used for the construction of the pupil in various medical treatments.

In 2022, an estimated 4.2 million Americans were living with glaucoma, a leading cause of irreversible blindness [1.2.1]. This article explores a key class of drugs used in its treatment and answers: what is an example of a miotic drug?

Opioids are one of the most common drug classes known to cause constricted pupils (miosis) by affecting the central nervous system. Understanding which medication causes the pupil to constrict is crucial for both medical professionals and patients to identify potential drug effects and overdoses.

While miosis is a well-known sign of opioid toxicity, it is not a typical side effect of standard olanzapine therapy. However, reports confirm that a moderate to severe olanzapine overdose frequently causes pupil constriction, often accompanied by fluctuating levels of consciousness.

Myasthenia gravis, a primary condition treated with neostigmine, affects an estimated 14 to 20 per 100,000 people in the United States [1.6.2]. A key question for this medication is, **does neostigmine cause miosis or mydriasis?** The answer lies in its pharmacological action.

Pinpoint pupils, medically known as miosis, are a classic sign of an opioid overdose, but this is not the only cause [1.2.8]. Numerous prescription and non-prescription drugs can lead to this condition. So, **what medications cause miosis?**

**Fact:** The iris sphincter muscle contains muscarinic acetylcholine receptors, and stimulating them is the specific mechanism by which **cholinergics constrict pupils**. This action, known as miosis, is a key function of the parasympathetic nervous system.

Pilocarpine has been used in ophthalmology for over a century and is the archetypal direct-acting parasympathomimetic agent. A definitive answer to the question, "Do pilocarpine eye drops dilate or constrict?", is that they cause **constriction** of the pupil, a process known as miosis.