Echothiophate Iodide

Mechanism of Action

Cholinesterase inhibitor; enhances activity of endogenous acetylcholine, which leads to continuous stimulation of the ciliary muscle producing miosis and fascilitation of humor outflow that may reduce intraocular pressure

Pharmacokinetics

Onset of action: 10-30 min (miosis); 4-8hr (IOP); 24 hr (peak effects IOP)

Duration: 1-4 weeks (miosis)

• It is used to treat glaucoma.
• It is used to treat cross-eyed children.

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

• Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
• Change in eyesight, eye pain, or very bad eye irritation.
• Fast or slow heartbeat.
• A heartbeat that does not feel normal.
• Loose stools (diarrhea).
• Trouble passing urine.
• Drooling.
• Muscle weakness.
• Sweating a lot.
• Shortness of breath.

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

• Eye irritation.
• Burning.
• Stinging.
• Tearing.
• Eye redness.
• Blurred eyesight.
• Eyelid twitching.
• Headache.

These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.

You may report side effects to the FDA at 1-800-FDA-1088. You may also report side effects at http://www.fda.gov/medwatch.

Accommodative esotropia: Ophthalmic:

Diagnosis: Instill 1 drop (0.125%) once daily into both eyes at bedtime for 2 to 3 weeks

Treatment: Usual dose: 1 drop of 0.06% once daily or 0.125% every other day (maximum: 1 drop of 0.125% in both eyes/day). Note: Use lowest concentration and frequency that gives satisfactory response; 0.3% has been proven to be effective.

Frequency not defined.

Cardiovascular: Bradycardia, cardiac abnormality, flushing, hypotension

Central nervous system: Brow ache, myasthenia

Dermatologic: Diaphoresis

Gastrointestinal: Diarrhea, nausea, vomiting

Ophthalmic: Blepharospasm, blurred vision, burning sensation of eyes, cataract, conjunctival abnormalities (thickening), conjunctival erythema, eye redness, increased intraocular pressure (paradoxical), iris cyst, iritis (latent), lacrimal duct obstruction (nasolacrimal canal), lacrimation, miosis, myopia, retinal detachment, stinging of eyes, uveitis (activation)

Respiratory: Dyspnea

Concerns related to adverse effects:

• Cardiac irregularities: Temporarily or permanently discontinue if cardiac irregularities occur.

• Cholinergic effects: Discontinue if symptoms of excess cholinergic activity (eg, salivation, sweating, urinary incontinence); overdosage may result in cholinergic crisis, which must be distinguished from myasthenic crisis.

Disease-related concerns:

• Asthma: Not generally recommended for use in patients with asthma.

• Cardiovascular disease: Not generally recommended for use in patients with bradycardia, hypotension or recent MI. In a scientific statement from the American Heart Association, ophthalmic cholinergic agents have been determined to be agents that may exacerbate underlying myocardial dysfunction (magnitude: minor) (AHA [Page 2016]).

• Gastrointestinal disease: Not generally recommended for use in patients with spastic gastrointestinal disturbances or peptic ulcer disease.

• Parkinsonism: Not generally recommended for use in patients with Parkinsonism.

• Seizure disorder: Not generally recommended for use in patients with a history of seizure disorder.

• Vagotonia: Not generally recommended for use in patients with vagotonia.

Concurrent drug therapy issues:

• Drug-drug interactions: Potentially significant interactions may exist, requiring dose or frequency adjustment, additional monitoring, and/or selection of alternative therapy. Consult drug interactions database for more detailed information.

Other warnings/precautions:

• Appropriate use: Do not use for tonometric glaucoma, or in patients with active or history of uveitis, or history of retinal detachment. Use cautiously prior to ophthalmic surgery due to risk of blood in the anterior chamber. Compress the nasolacrimal ducts for 1 to 2 minutes following instillation to minimize drainage into the nasal chamber. Wash hands following instillation.

• Exposure to pesticides and insecticides: Use with caution in patients exposed to carbamate- or organophosphate-type insecticides and pesticides; absorption of the pesticide through skin or respiratory tract may result in additive systemic effects; respiratory masks and frequent clothing changes may be necessary during exposure to pesticides in patients receiving echothiophate iodide.

• Tolerance: Patients may develop tolerance after prolonged use; a rest period restores response to the drug.

Animal reproduction studies have not been conducted.

• Discuss specific use of drug and side effects with patient as it relates to treatment. (HCAHPS: During this hospital stay, were you given any medicine that you had not taken before? Before giving you any new medicine, how often did hospital staff tell you what the medicine was for? How often did hospital staff describe possible side effects in a way you could understand?)

• Patient may experience burning, stinging, blurred vision, headache, eye redness, eyelid twitching, or watery eyes. Have patient report immediately to prescriber vision changes, eye pain, severe eye irritation, tachycardia, bradycardia, abnormal heartbeat, diarrhea, difficult urination, drooling, muscle weakness, sweating a lot, or shortness of breath (HCAHPS).

• Educate patient about signs of a significant reaction (eg, wheezing; chest tightness; fever; itching; bad cough; blue skin color; seizures; or swelling of face, lips, tongue, or throat). Note: This is not a comprehensive list of all side effects. Patient should consult prescriber for additional questions.

Intended Use and Disclaimer: Should not be printed and given to patients. This information is intended to serve as a concise initial reference for health care professionals to use when discussing medications with a patient. You must ultimately rely on your own discretion, experience, and judgment in diagnosing, treating, and advising patients.

Substance Name

Echothiophate

CAS Registry Number

513-10-0

Drug Class

Cholinesterase Inhibitors

Miotics

Parasympathomimetics