PHENYLEPHRINE 10 MG/ML INJECTION
Active substance(s): PHENYLEPHRINE HYDROCHLORIDE
NAME OF THE MEDICINAL PRODUCT
Phenylephrine 10 mg/ml Injection
QUALITATIVE AND QUANTITATIVE COMPOSITION
Each 1 ml ampoule contains 10 mg of the active ingredient phenylephrine hydrochloride.
Excipients with known effect:
Sodium hydroxide solution (q.s.- quantity per ml)
For the full list of excipients, see section 6.1.
A clear, colourless sterile solution
Phenylephrine Injection is indicated in adults and children for the treatment of
hypotensive states e.g. circulatory failure, during spinal anaesthesia or drug induced
Posology and method of administration
Phenylephrine Injection may be administered subcutaneously or intramuscularly in a
dosage of 2 to 5 mg with further doses of 1 to 10 mg if necessary according to response,
or in a dose of 100 to 500 micrograms by slow intravenous injection as a 0.1% solution,
repeated as necessary after at least 15 minutes.
Alternatively, 10 mg in 500 ml of glucose 5% injection or sodium chloride 0.9% injection
may be infused intravenously, initially at a rate of up to 180 micrograms per minute,
reduced according to response to 30-60 micrograms per minute.
100 mcg/kg body weight subcutaneously or intramuscularly.
There is no need for dosage reduction in the elderly.
Method of administration
For subcutaneous, intramuscular, slow intravenous injection or intravenous infusion.
Hypersensitivity to phenylephrine or to any of the excipients listed in section 6.1.
Patients taking monoamine oxidase inhibitors, or within 14 days of ceasing such
Severe hypertension and hyperthyroidism.
Special warnings and precautions for use
Great care should be exercised in administering Phenylephrine Injection to patients with preexisting cardiovascular disease such as ischaemic heart disease, arrhythmias, occlusive vascular
disease including arteriosclerosis, hypertension or aneurysms. Anginal pain may be precipitated
in patients with angina pectoris.
Care is also required when given to patients with diabetes mellitus, or closed angle glaucoma.
Keep all medicines out of the reach of children.
Phenylephrine Injection contains sodium.
This medicinal product contains less than 1 mmol sodium (23 mg) per dose, i.e. essentially
Interaction with other medicinal products and other forms of interaction
Phenylephrine may interact with cyclopropane and halothane and other halogenated inhalational
anaesthetics, to induce ventricular fibrillation. An increased risk of arrhythmias may also occur if
phenylephrine injection is given to patients receiving cardiac glycosides, quinidine or tricyclic
Phenylephrine is a hypertensive agent and may consequently reverse the action of many
antihypertensive drugs. Interactions of phenylephrine with alpha and beta receptor blocking drugs
may be complex.
Drugs which have an effect on α1 adrenoceptors could potentiate (such as clonidine) or inhibit
(such as doxazosin) the vasopressive action of phenylephrine.
Caution should be applied when administering atomoxetine concurrently, as there is potential for
synergistic pharmacological effects.
Severe hypertension may occur following the use of phenylephrine and atropine or other
The pressor effects of phenylephrine may be slightly reduced by lithium carbonate.
The effects of phenylephrine may be potentiated by the use of monoamine oxidase inhibitors or
reversible inhibitors of monoamine oxidase.
Fertility, pregnancy and lactation
The safety of phenylephrine during pregnancy has not been established. Due to the
vasoconstrictive properties of phenylephrine, the product should be used with caution in
patients with a history of pre-eclampsia. Administration of phenylephrine in late
pregnancy or labour may cause foetal hypoxia and bradycardia.
The safety of phenylephrine during lactation has not been established. Excretion of
phenylephrine in breast milk appears to be minimal.
Effects on ability to drive and use machines
No adverse effects known.
Immune system disorders
Metabolism and nutrition disorders
Nervous system disorders
Headache, cerebral haemorrhage, paraesthesia
Mydriasis, angle-closure glaucoma
Pulmonary oedema, bradycardia, tachycardia, arrhythmia, angina pectoris, palpitations, cardiac
Hypotension, dizziness, syncope, flushing
Respiratory, thoracic and mediastinal disorders
Vomiting, salivary hypersecretion
Renal and urinary disorders
Dysuria, urinary retention
General disorders and administration site conditions
Extravasation, infusion site necrosis, hyperhidrosis
Increased blood pressure, abnormal blood glucose
Phenylephrine is without significant stimulating effects on the central nervous system at usual
Reporting of suspected adverse reactions
Reporting suspected adverse reactions after authorisation of the medicinal product is important. It
allows continued monitoring of the benefit/risk balance of the medicinal product. Healthcare
professionals are asked to report any suspected adverse reactions via the Yellow Card Scheme
Symptoms of overdosage include headache, vomiting, hypertension and reflex
bradycardia and other cardiac arrhythmias. In severe cases confusion, hallucinations and
seizures may occur.
Treatment should consist of symptomatic and supportive measures. The hypertensive
effects may be treated with an alpha adrenoreceptor blocking drug, such as phentolamine,
5 to 60 mg i.v. over 10-30 minutes, repeated as necessary.
Pharmacotherapeutic group: adrenergic and dopaminergic agent
ATC code: C01CA
Phenylephrine hydrochloride is a sympathomimetic agent with mainly direct effects on
adrenergic receptors. It has predominantly alpha-adrenergic activity and is without significant
stimulating effects on the central nervous system at usual doses.
Mechanism of action
After injection it produces peripheral vasoconstriction and increased arterial pressure; it also
causes reflex bradycardia.
When injected subcutaneously or intramuscularly, phenylephrine takes 10 to 15 minutes
to act. Subcutaneous and intramuscular injections are effective for up to about one and
up to about two hours respectively. Intravenous injections are effective for up to about
Phenylephrine is metabolised in the liver by monoamine oxidase.
The metabolites, their route and rate of excretion have not been identified.
Preclinical safety data
Phenylephrine has been used to induce cardiac myocyte hypertrophy in cultures of rat
neonatal mycocytes at doses of 100 µM and 10 µM. To the best of our knowledge there
have been no human studies associating therapeutic phenylephrine use with the
development of cardiac myocyte hypertrophy
List of excipients
Sodium Hydroxide solution 1N
Hydrochloric Acid 36% 1N
Water for injections
Phenylephrine Injection has been stated to be incompatible with alkalies, ferric
salts, phenytoin sodium and oxidising agents.
Special precautions for storage
Store at 2-25°C. Protect from light
Nature and contents of container
1 ml neutral glass ampoule with red imprint break ring.
Pack size: 6 x 1ml and 10 x 1ml ampoules
Not all pack sizes may be marketed.
Special precautions for disposal
No special requirements.
MARKETING AUTHORISATION HOLDER
Amdipharm UK Limited
85 King William Street,
London EC4N 7BL, UK
MARKETING AUTHORISATION NUMBER(S)
DATE OF FIRST AUTHORISATION/RENEWAL OF AUTHORISATION
Date of first authorisation: 17 November 1999
Date of latest renewal: 18 November 2005
DATE OF REVISION OF THE TEXT
Source: Medicines and Healthcare Products Regulatory Agency
Disclaimer: Every effort has been made to ensure that the information provided here is accurate, up-to-date and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. This information has been compiled for use by healthcare practitioners and consumers in the United States. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate that the drug or combination is safe, effective or appropriate for any given patient. If you have questions about the substances you are taking, check with your doctor, nurse or pharmacist.