Phenylephrine

Registered South African indications:

• Mydriasis

Contraindications

• Hypersensitivity to the active ingredient or any of its excipients
• Children (10% sol.)
• Newborns and infants with cardio- and cerebrovascular disease
• Elderly (10% sol.)
• Elderly with severe arteriosclerotic, cardiovascular or cerebrovascular disease (2.5% sol.)
• Closed angle glaucoma (unless previously treated with iridectomy)
• Patients with narrow angle prone to glaucoma precipitated by mydriatics  
• Cardiac disease
• Hypertension
• Aneurysms
• Thyrotoxicosis
• Long-standing insulin dependent diabetes mellitus
• Tachycardia
• Coadministration with monoamine oxidase inhibitors
• Coadministration with tricyclic antidepressants
• Coadministration with antihypertensive agents (including beta blockers)

Cautions

• Pregnancy
• Breastfeeding
• Elderly (2.5% sol.)
• Preterm, low birth weight and newborn infants (2.5% sol.)
• Diabetes mellitus
• Cerebral arteriosclerosis
• Asthma
• Denuded or damaged corneal epithelium
• Ocular hyperaemia
• May impair ability to drive and operate machinery

Forms avail. in SA and covered in this monograph: opd

Diagnostic mydriasis

• Ophthalmic (opd): 2.5% sol and 10% sol. 1-2 drops into each eye(s), 30-60min before procedure; Max: 3 drops per eye/24hrs

Can cause intense irritation and a local anaesthetic should be instilled a few minutes before application

Minimise systemic absorption by compressing the lacrimal sac at the medial canthus for 1 minute after instillation

Paed. forms avail. in SA and covered in this monograph: opd

Diagnostic mydriasis

Younger than 1 year

• Ophthalmic (opd): 2.5% sol. 1-2 drops into each eye(s), 30-60min before procedure; Max: 3 drops per eye/24hrs

Older than 1 year

• See adult dosage

Do NOT use 10% sol. in infants

 Beware of inducing apnoea in infants

Can cause intense irritation and a local anaesthetic should be instilled a few minutes before application

Minimise systemic absorption by compressing the lacrimal sac at the medial canthus for 1 minute after instillation

Phenylephrine 2.5%w/v eye drops may be combined with other mydriatics/cycloplegics to produce adequate mydriasis/cycloplegia

Heavily pigmented irides may require larger doses and caution should be exercised to avoid overdosage

Pregnancy

• Caution
• Safety for use in pregnancy has not been established. This product should only be used during pregnancy if it is considered to be essential

Breastfeeding

• Caution
• Safety for use in breastfeeding women has not been established

Renal Impairment

• No dose adjustment recommended

Hepatic Impairment

• No dose adjustment recommended

Elderly

• 2.5% sol: Caution; no dose adjustment recommended
  Contraindicated in elderly adults with severe arteriosclerotic, cardiovascular or cerebrovascular disease
• 10% sol: Contraindicated

Porphyria Information

• Probably not porphyrinogenic (PNP)

Drugs in Sport

• Permitted - No warnings

Cardiovascular Disorders

• Tachycardia
• Palpitations
• Extrasystoles
• Arrhythmias
• Ventricular arrhythmia
• Arteriospasm coronary
• Myocardial infarction
• Hypertension

Respiratory Disorders

• Pulmonary oedema (paediatrics)
• Respiratory, thoracic and mediastinal disorders (paediatrics)

Immune, Blood and Lymphatic System Disorders

• Hypersensitivity reactions

Sensory Disorders

• Eye pain
• Eye irritation
• Blurred vision
• Photophobia
• Allergic conjunctivitis

• Antihypertensives
• Tricyclic antidepressants
• Monoamine oxidase inhibitors
• General anaesthetics
• Halothane
• Cardiac glycosides
• Quinidine

None routine

Paediatric population (2.5% sol.)

• The lowest dose necessary to produce the desired effect should always be used
• Parents should be warned not to get this preparation in their children's mouth or cheeks and to wash their hands and the child's hands or cheeks following administration
• The use in preterm and newborn infants is not recommended unless clearly necessary and only with caution because of safety concerns associated with the risk of systemic adverse reactions including transient increases in blood pressure
• If treatment is medically justified the lowest possible concentration and dose should be used and instillation of more than one drop per eye must be avoided

Phenylephrine is a direct acting sympathomimetic agent. It causes mydriasis via the stimulation of alpha receptors. There is almost no cycloplegic effect.

Eye drops (per 0.5ml) 50mg

• Minims Phenylephrine Hydrochloride 10% (Soflens) originator

Eye drops (per ml) 100mg

• Phenylephrine Covan (Adcock) originator

Also available in the following forms: Nasal spray, drops, tablet, syrup and injection.

COMBINATION PREPARATIONS

Cyclopentolate/ Phenylephrine

Drop (per ml) 2mg/1%

• Cyclomydril (Alcon) originator