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Clonidine hydrochloride


Solution for injection containing clonidine hydrochloride 150micrograms per 1ml.

Drugs List

  • CATAPRES 150microgram/1ml injection
  • clonidine 150microgram/1ml injection
  • Therapeutic Indications


    Treatment of hypertensive crisis.



    150micrograms to 300micrograms administered by slow intravenous injection.
    Dose may be repeated, but should not exceed a maximum of 750micrograms in a 24 hour period.


    Children aged 2 to 18 years (unlicensed)
    2micrograms/kg to 6micrograms/kg as a single dose.
    Maximum dose should not exceed 300micrograms.

    Patients with Renal Impairment

    Clonidine should be used with caution in patients with renal failure. Clonidine is excreted extensively in the urine. Dosage must be adjusted to the individuals antihypertensive response and degree of renal impairment. Careful monitoring of these patients is required.

    No additional clonidine support is required during haemodialysis as only a minimal amount is removed during the procedure.

    The Renal Drug Handbook suggests the following doses:

    GFR (ml/minute)
    20ml/minute to 50ml/minute - Dose as in normal renal function.
    10ml/minute to 20ml/minute - Dose as in normal renal function.
    Less than 10ml/minute - Dose as in normal renal function.

    Additional Dosage Information

    Patients undergoing anaesthesia should continue clonidine therapy before, during and after anaesthesia. Clonidine may be given to these patients in the intravenous or oral tablet form depending on individual circumstances.


    To be administered via slow intravenous injection over 10 to 15 minutes to avoid a possible transient pressor effect.


    Clonidine hydrochloride solution is compatible with 0.9% sodium chloride solution and 5% dextrose solution.


    Children under 2 years
    Severe bradycardia due to sick sinus syndrome or an AV block of the 2nd or 3rd degree
    Breastfeeding (see Lactation)

    Precautions and Warnings

    Use with caution in children aged 2 - 18 years (see Dosage - Children ).

    Use with caution in patients with renal impairment (see Dosage - Renal Impairment ).

    Caution if treating patients with current or a history of depression due to reports of further depressive episodes.

    Use with caution in patients with the following conditions:
    Cerebrovascular or coronary impairment
    Raynaud's disease
    Peripheral vascular occlusive disease
    Ischaemic heart disease, including myocardial infarction
    Mild to moderate bradycardias e.g. low sinus rhythm

    Patients who wear contact lenses should be warned that treatment with clonidine may cause decreased lacrimation.

    Alcohol can be potentiated by clonidine.

    Side effects such as drowsiness and sedation may affect the patients ability to drive or to operate machinery.

    Monitor treatment in patients with cardiac failure.

    Patients undergoing anaesthesia should continue their clonidine treatment before, during and after anaesthesia using oral or i.v. administration according to individual circumstances.

    No therapeutic effect can be expected for hypertension caused by phaeochromocytoma.

    If given with a concurrent beta blocker, do not withdraw clonidine until several days after withdrawal of the beta blocker.

    Pregnancy (see Pregnancy ).

    Non-steroidal anti-inflammatory (NSAIDs) agents can reduce the therapeutic effect of clonidine.

    Pregnancy and Lactation


    Only use clonidine during pregnancy if essential. If clonidine is used during pregnancy it is recommended that the mother and child are monitored. Clonidine passes the placental barrier and may lower the heart rate of the foetus. Post partum a transient rise in blood pressure in the newborn cannot be excluded. There are no data on the long-term effects of pre-natal exposure. Schaeffer (2007) considered clonidine to be a second line choice for treatment of hypertension during pregnancy but states that there is insufficient evidence for its use in migraine during pregnancy. Intravenous injection of clonidine should be avoided during pregnancy.

    The use of all medication in pregnancy should be avoided whenever possible; particularly in the first trimester. Non-drug treatments should also be considered. When essential, a medication with the best safety record over time should be chosen, employing the lowest effective dose for the shortest possible time. Polypharmacy should be avoided. Teratogens taken in the pre-embryonic period, often quoted as lasting until 14-17 days post-conception, are believed to have an all-or-nothing effect. Where drugs have a short half-life, and when the date of conception is certain, this may allow women to be reassured where drug exposure has occurred within this time frame. Further advice may be available from the UK National Teratology Information Service (NTIS) and through ToxBase, available via password on the internet ( ) or if this is unavailable at the backup site ( ).

    Licensed in pregnancy? - No

    Recommended for use in pregnancy? - No

    Known human teratogen? - No

    Crosses placenta? - Yes

    Effects on foetus - May lower foetal heart rate. Post-partum, a transient rise in blood pressure in the newborn cannot be excluded.


    Contraindicated in breastfeeding due to inadequate evidence of safety. Clonidine is secreted into the breast milk. Schaeffer (2007) states that clonidine at the usual maternal doses used for hypertension reaches near therapeutic levels in the breast fed infant, although no adverse effects have been reported. it is recommended that clonidine is not used during breastfeeding, but if already started, weaning is not necessary but the maternal therapy should be changed to a preferred drug for the indication.

    Clonidine has complex dose related actions in both oxytocin and prolactin secretion which may affect lactation.

    Neonates, infants born prematurely, those with low birth weight, those with an unstable gastrointestinal function or who have serious illnesses may require special consideration. For any infant, if a drug is prescribed to the nursing mother, it should be at the lowest practical dose and for the shortest time. When drug administration is unavoidable and breastfeeding is to continue, minimisation of exposure of the infant to the drug may sometimes be achieved by timing the maternal doses to just after a feeding episode. Infants exposed to drugs via breast milk should be monitored for unusual signs or symptoms. Interactions between the drug received by the infant from the mother's milk and medication prescribed for the infant should also be considered, for example, when the drug given to the infant may prevent metabolism of the drug received via breast milk.
    Specialist advice is available from the UK Drugs in Lactation Advisory Service at

    Drug excreted in breast milk? - Yes

    Considered suitable or recommended by manufacturer? - No

    Drug substance licensed in infants? - No

    Effects on Ability to Drive and Operate Machinery

    Side effects such as drowsiness and sedation may affect the patient's ability to drive or operate machinery.


    Advise patients not to drive or operate machinery if affected by side effects such as drowsiness and sedation.

    Advise contact lens wearers that treatment with clonidine may reduce lacrimation.

    Advise patients to moderate alcohol intake.

    Advise patients not to self administer NSAIDs unless under the guidance of a clinician.

    Side Effects

    Dry mouth
    Fluid retention
    Sinus bradycardia
    Raynaud's phenomenon
    Urinary retention
    Decreased lacrimation
    Reduced libido
    Orthostatic hypotension
    Paraesthesia in extremities
    Pain in parotid gland
    Dryness of nasal mucosa
    Sleep disturbances
    Perceptual disturbances
    ECG changes
    Abnormal liver function tests
    Elevated blood glucose (transient)
    Disturbances in accommodation
    Pseudo-obstruction of the large intestine
    Atrioventricular block
    Dryness and irritation of eyes


    It is strongly recommended that the UK National Poisons Information Service be consulted on cases of suspected or actual overdose where there is doubt over the degree of risk or about appropriate management.

    The following number will direct the caller to the relevant local centre (0844) 892 0111

    Information may be obtained if you have access to ToxBase the primary clinical toxicology database of the National Poisons Information Service. This is available via password on the internet ( ) or if this is unavailable at the backup site ( ).

    Shelf Life and Storage

    Do not store above 30 degrees C.
    Keep container in outer carton.

    Further Information

    Last Full Review Date: June 2012

    Reference Sources

    Drugs During Pregnancy and Lactation: Treatment Options and Risk Assessment, 2nd edition (2007) ed. Schaefer, C., Peters, P. and Miller, R. Elsevier, London.

    Drugs in Pregnancy and Lactation: A Reference Guide to Fetal and Neonatal Risk, 9th edition (2011) ed. Briggs, G., Freeman, R. and Yaffe, S. Lippincott Williams & Wilkins, Philadelphia.

    Martindale: The Complete Drug Reference, 37th edition (2011) ed. Sweetman, S. Pharmaceutical Press, London.

    Summary of Product Characteristics: Catapres ampoules. Boehringer Ingelheim Ltd. Revised May 2014.

    The Renal Drug Handbook. 3rd edition. (2009) ed. Ashley, C and Currie, A. Radcliffe Medical Press, Abingdon.

    US National Library of Medicine. Toxicology Data Network. Drugs and Lactation Database (LactMed).
    Available at:
    Clonidine Last revised: April 3, 2012
    Last accessed: June 19, 2012

    NICE Evidence Services Available at: Last accessed: 17 August 2017

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