PHENYLEPHRINE

Posology Adults Normal dose is 50 to 100 micrograms, which can be repeated until the desired effect is obtained. One bolus dose should not exceed 100 micrograms. Renal impairment Lower doses of phenylephrine may be needed in patients with impaired renal function.

Hepatic Impairment Higher doses of phenylephrine may be needed in patients with cirrhosis of the liver.

Elderly:

Treatment of the elderly should be carried out with care. Paediatric population The safety and efficacy of phenylephrine in children have not been established. No data are available.

Method of administration:

Intravenous bolus injection. Phenylephrine, 50 micrograms/ml, solution for injection should only be administered by healthcare professionals with appropriate training and relevant experience. The pre-filled syringe is not suitable for use in a syringe driver.

Summary of the safety profile The most common adverse events of phenylephrine are bradycardia, hypertensive episodes, nausea and vomiting. Hypertension is more frequent with high doses. The most commonly reported cardiovascular adverse event appears to be bradycardia, likely due to baroreceptor-mediated vagal stimulation and consistent with the pharmacological effect of phenylephrine.

List of adverse reactions Frequency:

Not known (cannot be estimated from available data) Immune system disorders: Not known: hypersensitivity Psychiatric disorders: Not known: Anxiety, excitability, agitation, psychotic states, confusion.

Nervous system disorders Not known:

Headache, nervousness, insomnia, paresthesia, tremor.

Eye disorders:

Not known: Mydriasis, aggravation of pre-existing angle-closure glaucoma Cardiac disorders: Not known: Reflex bradycardia, tachycardia, palpitations, hypertension, arrhythmia, angina pectoris, myocardial ischemia.

Vascular disorders:

Not known: Cerebral haemorrhage, hypertensive crisis Respiratory, thoracic and mediastinal disorders: Not known: Dyspnoea, pulmonary oedema Gastrointestinal disorders: Not known: Nausea, vomiting Skin and subcutaneous tissue disorders: Not known: Sweating, pallor or skin blanching, piloerection, skin necrosis with extravasation Musculoskeletal and connective tissue disorders: Not known: muscular weakness Renal and urinary disorders: Not known: Difficulty in micturition and urinary retention Description of selected adverse reactions As phenylephrine has been frequently used in the critical care setting in patients with hypotension and shock, some of the reported serious adverse events and deaths are probably related to the underlying disease and not related to the use of phenylephrine.

The arterial blood pressure should be monitored during treatment. Phenylephrine should be administered with care to patients with: - diabetes mellitus; - arterial hypertension; - uncontrolled hyperthyroidism; - coronary heart disease and chronic heart conditions; - non-severe peripheral vascular insufficiency, - bradycardia; - partial heart block; - tachycardia; - arrhythmias; - angina pectoris (phenylephrine can precipitate or exacerbate angina in patients with coronary artery disease and history of angina); - aneurysm; - closed angle glaucoma.

Phenylephrine can induce a reduction in cardiac output. Therefore, care should be exercised in administering to patients with arteriosclerosis, the elderly and to patients with impaired cerebral or coronary circulation. In patients with reduced cardiac output or coronary vascular disease, vital organ functions should be closely monitored and dose reduction should be considered when systemic blood pressure is near the lower end of the target range.

In patients with serious heart failure or cardiogenic shock, phenylephrine may cause deterioration in the heart failure as a consequence of the induced vasoconstriction (increase in afterload). Particular attention should be paid when administering Phenylephrine injection to avoid extravasation, since this may cause tissue necrosis.

9 % of the WHO recommended maximum daily intake of 2 g sodium for an adult.

5); - in patients with severe hyperthyroidism.