Drug Guide
Tetracaine Hydrochloride
Classification
Therapeutic: Local Anesthetic
Pharmacological: Ester-type local anesthetic
FDA Approved Indications
- Topical anesthesia for ophthalmic, otic, dermal, and mucous membrane procedures
Mechanism of Action
Tetracaine inhibits nerve impulse initiation and conduction by reversibly blocking sodium channels in neuronal membranes, preventing depolarization.
Dosage and Administration
Adult: Typically applied topically in doses appropriate for the procedure, e.g., ophthalmic drops or ointments as prescribed.
Pediatric: Doses vary based on age and procedure; consult specific guidelines.
Geriatric: Adjust dose if necessary due to increased sensitivity and potential comorbidities.
Renal Impairment: Use with caution; no specific dosage adjustment established.
Hepatic Impairment: Use with caution; no specific dosage adjustment established.
Pharmacokinetics
Absorption: Minimal when applied topically; absorption may occur in mucous membranes.
Distribution: Widely distributed in tissues; crosses mucous membranes.
Metabolism: Metabolized in the liver primarily via plasma cholinesterases.
Excretion: Excreted in urine.
Half Life: Approximately 1-2 hours when administered locally.
Contraindications
- Hypersensitivity to tetracaine or other ester anesthetics.
- Patients with known allergies to local anesthetics.
Precautions
- Use cautiously in patients with nasal infections or mucosal damage, as systemic absorption may be increased.
Adverse Reactions - Common
- Local irritation, burning or stinging at application site (Common)
- Allergic contact dermatitis (Less common)
Adverse Reactions - Serious
- Anaphylaxis (Rare)
- Methemoglobinemia (especially with overdose or systemic absorption) (Rare)
Drug-Drug Interactions
- Other ESTER-type local anesthetics may increase risk of toxicity.
Drug-Food Interactions
- None significant.
Drug-Herb Interactions
- Limited data; use caution with herbal products affecting bleeding or wound healing.
Nursing Implications
Assessment: Monitor for allergic reactions, wound healing, and systemic toxicity signs.
Diagnoses:
- Risk of allergic reaction,
- Impaired skin integrity,
- Risk of systemic toxicity.
Implementation: Apply as prescribed, in correct dosage and technique. Avoid exceeding recommended dose.
Evaluation: Assess for effectiveness, adverse reactions, and signs of toxicity.
Patient/Family Teaching
- Instruct to report any allergic reactions or unusual sensations.
- Advise on proper application and avoiding excessive use.
Special Considerations
Black Box Warnings:
- None currently, but caution with systemic absorption and allergy.
Genetic Factors: None established.
Lab Test Interference: None known.
Overdose Management
Signs/Symptoms: Signs of systemic toxicity include dizziness, tinnitus, seizures, difficulty breathing, and cyanosis.
Treatment: Supportive care, airway management, and administration of lipid emulsion therapy if indicated.
Storage and Handling
Storage: Store at room temperature, away from heat and moisture.
Stability: Stable under recommended storage conditions.