Tag: Miotics

Pilocarpine, a muscarinic receptor agonist, causes pupil constriction by stimulating the iris sphincter muscle. This primary action, known as miosis, has been leveraged in ophthalmology for over a century to treat various eye conditions, including certain types of glaucoma and, more recently, presbyopia. Its miotic effects are the central focus of its therapeutic application in eye care.

As of 2022, an estimated 4.2 million Americans live with glaucoma, a leading cause of irreversible blindness [1.7.2, 1.7.1]. A foundational question in its treatment is, 'What cholinergic drug causes miosis and is used in the treatment of glaucoma?' The answer is primarily Pilocarpine [1.2.2].

More than 70 years ago, cholinesterase inhibitors were introduced as a way to treat glaucoma by lowering intraocular pressure (IOP). This class of medication is known for its indirect action, which helps increase the outflow of fluid from the eye through a specific biological pathway controlled by acetylcholine.

The size of our pupils is regulated by the autonomic nervous system, and approximately 55% of patients in one ICU study showed smaller pupils when receiving fentanyl, an opioid. A notable side effect of several drug classes is pupillary constriction (miosis), and understanding which group of medications causes pupillary constriction is critical for accurate diagnosis and clinical management, especially in overdose situations.

During delicate eye surgeries, controlling the size of the pupil is essential for surgical success and safety. This is achieved using miotic agents, which are a specific type of drug that constrict the pupil during ophthalmic surgery, enabling surgeons to work more precisely and efficiently. A prominent example is acetylcholine chloride, which is delivered directly into the eye for rapid and short-lived pupil constriction.

With millions of people affected, glaucoma is a serious eye condition often managed by controlling intraocular pressure (IOP) to prevent vision loss. Cholinergic drugs help with glaucoma by targeting the eye's natural drainage system to increase fluid outflow and reduce this pressure.

Mydriatic eye drops are used by eye doctors to purposefully enlarge or dilate the pupils. This process, known as mydriasis, is crucial for allowing a comprehensive examination of the eye's internal structures, including the retina and optic nerve.

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.

With a history in eye care spanning over 100 years, miotic drugs have long been an essential tool for managing various ocular conditions. This guide will answer the question, "What drugs are miotics?" by exploring their mechanisms, common uses, classifications, and important safety considerations.

Affecting over a billion people globally, presbyopia is a ubiquitous age-related condition that causes blurry near vision. Pharmacologic approaches to presbyopia correction are based on two main mechanisms: using miotic agents to create a pinhole effect and, in a less developed field, employing lens softeners to restore elasticity. These eye drops offer a non-invasive alternative to glasses or surgery for improving near and intermediate vision.