Ocular Cyclopentolate: A Mini Review Concerning Its Benefits and Risks

Abstract

Cycloplegic and mydriatic agents are essential in ophthalmological clinical practice since they provide the means for diagnosing and treating certain eye conditions. In addition, cyclopentolate has proven to possess certain benefits compared to other available cycloplegics and mydriatics. Still, the incidence of some adverse drug reactions related to this drug, especially in susceptible patients, has created interest in reviewing the literature about the benefits and risks of using cyclopentolate. A literature search was conducted in Medline/PubMed and Google Scholar, focusing on identifying cyclopentolate’s benefits and risks; the most important benefit was its usefulness for evaluating refractive errors, especially for hyperopic children, pseudomyopia, anterior uveitis, treatment of childhood myopia, idiopathic vision loss, and during examinations before refractive surgery, with particular advantages compared to other cycloplegics. While the risks were divided into local adverse drug reactions such as burning sensation, photophobia, hyperemia, punctate keratitis, synechiae, and blurred vision, which are relatively frequent but mild and temporary; and systemic adverse drug reactions such as language problems, visual or tactile hallucinations and ataxia, but unlike ocular, systemic adverse drug reactions are rare and occur mainly in patients with risk factors. In addition, six cases of abuse were found. The treatment with cyclopentolate is effective and safe in most cases; nevertheless, special care must be taken due to the potential severe ADRs that may occur, especially in susceptible patients like children, geriatrics, patients with neurological disorders or Down’s syndrome, patients with a low blood level of pseudocholinesterase, users of substances with CNS effects, and patients with a history of drug addiction. The recommendations are avoiding the use of 2% cyclopentolate and instead employing solutions with lower concentrations, preferably with another mydriatic such as phenylephrine. Likewise, the occlusion of the nasolacrimal duct after instillation limits the drug’s absorption, reducing the risk of systemic adverse events.

Pharmacologic Mydriasis and Cycloplegia: A Review of Novel Delivery Devices

“…31 The side-effect profile of this medication is quite similar to other antimuscarinic agents and may increase intraocular pressure (IOP), cause irritation and conjunctival hyperemia and, rarely, central nervous system effects such as restlessness, hyperactivity and ataxia. 32,33 Phenylephrine is an alpha-1 adrenergic receptor agonist, which acts by increasing sympathetic stimulation to the iris dilator, although it is not thought to have a major effect on accommodation. 34 Available doses are 1% (when delivered via combination drop with cyclopentolate), 2.5%, and 10%.…”

Study protocol: Accommodative effects on the musculoskeletal system

“…This proprietary study is designed to investigate the effects of accommodation on the musculoskeletal system. Five ocular mydriatics and cycloplegics are currently available [19]. Cyclopentolate was first synthesized in 1951 by Treves and Testa [20].…”

“…Cyclopentolate hydrochloride is a cholinolytic agent that blocks muscarinic acetylcholine receptors. Muscarinic acetylcholine receptors include a family of five G protein-coupled receptors [19]. All five subtypes of muscarinic receptors are present in the human eye, especially in the iris-ciliary body [21].…”

Comparative Analysis of Cycloplegia’s Effect on Intraocular Parameters in Keratoconus and Controls

“…This condition, typically emerging in adolescence or early adulthood, results in irregular astigmatism, myopia, and visual deterioration (4). Cycloplegia, the paralysis of the ciliary muscle responsible for lens accommodation, is induced via topical agents such as atropine and cyclopentolate (5,6). These agents inhibit muscarinic receptors within the ciliary muscle.…”