lidocaine hydrochloride + phenylephrine hydrochloride: clinical use

Prescribing considerations

• Confirm the indication and review all sympathomimetic-containing preparations, including nasal and eye products.
• Use caution with traumatised or septic mucosa because systemic absorption may increase.
• Assess cardiovascular disease, diabetes, hyperthyroidism, hypoxia, hypercapnia, porphyria, epilepsy, bradycardia, impaired conduction, hepatic impairment and severe shock.
• Account for impaired swallowing and biting trauma after pharyngeal or oral mucosal anaesthesia.
• Use for one patient only and discard remaining solution after the procedure session.

Contraindications and cautions

• Hypersensitivity to lidocaine, another amide local anaesthetic, phenylephrine or an excipient
• Pregnancy or breastfeeding
• Hypovolaemia, hypertension, acute ischaemic heart disease or complete heart block
• Thyrotoxicosis, glaucoma or urinary retention
• Use of other sympathomimetics
• Current or recent irreversible monoamine oxidase inhibitor treatment

Monitoring

• Observe blood pressure, pulse and rhythm where clinically appropriate.
• Watch for early central nervous system toxicity, including circumoral numbness, tinnitus, dizziness, tremor or agitation.
• Monitor swallowing and airway safety after pharyngeal application.
• Maintain readiness to manage seizures, respiratory depression and cardiovascular toxicity.

Clinical pharmacology

Lidocaine produces reversible local anaesthesia through voltage-gated sodium-channel blockade. Phenylephrine is predominantly a direct alpha-1 agonist that causes vasoconstriction; systemic absorption can produce hypertension, reflex bradycardia and arrhythmias.

Formulation and product differences

• This topical solution is intended for nasal and pharyngeal mucosa; it is not interchangeable with lidocaine skin preparations, injections or phenylephrine-only products.
• The spray container is a single-patient, single-session presentation.
• The listed excipients are water for injections with hydrochloric acid and sodium hydroxide for adjustment.