PHENYLEPHRINE HYDROCHLORIDE

Metaoxedrine

Reviewed by
September 1998
Administration Newborn Drug Protocol Index Newborn Services Home Page

Dose and Administration

  1. Instil one drop in each eye before eye examination as per the ROP guideline.

Indications

Is used in conjunction with cyclopentolate hydrochloride to dilate the pupil in preparation for eye examination.

  1. All babies at risk of severe ROP.
  2. Intraocular surgery pre and postoperatively.

Contraindications and Precautions

  1. Known hypersensitivity to phenylephrine.
  2. Severe hypertension, ventricular tachycardia.
  3. Caution in neonates with hyperthyroidism, hypertension, myocardial disease, heart block, bradycardia, bronchopulmonary dysplasia.

Clinical Pharmacology

Phenylephrine is a sympathomimetic agent with mainly direct effects on adrenergic receptors. Produces mydriasis without cycloplegia. It also acts as a conjunctival decongestant. The effect lasts several hours.

Phenylephrine may lower intraocular pressure temporarily.

Systemic absorption from conjunctival membranes can occur.

Possible Adverse Effect

  1. Reflex bradycardia, ventricular dysrhythmias, tachycardia.
  2. Excitability, headache, lacrimation, conjunctival allergy.
  3. Increase in blood pressure.
  4. May cause local discomfort.

Special Considerations

  1. Solutions stronger than 2.5% are NOT recommended in the newborn.
  2. Interactions - beta-blocker: may cause arrhythmias.
  3. See the ROP guideline.