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Clonidine oral


Oral formulations of clonidine hydrochloride.

Drugs List

  • clonidine 25microgram tablets
  • clonidine 50microgram/5ml oral solution sugar-free
  • Therapeutic Indications


    Management of vasomotor conditions (especially flushing) due to menopause
    Migraine (prophylaxis)
    Vascular headache: prophylaxis



    Initial dose: 50micrograms twice a day.
    If considered necessary, after 2 weeks, the dose may be increased to 75micrograms twice a day.


    Children under 18 years
    Severe bradycardia due to AV block (2nd/3rd degree)
    Severe bradycardia due to sinus node dysfunction

    Precautions and Warnings

    Acute porphyria
    Cardiac conduction defects
    Cardiac failure
    Cerebrovascular disorder
    Glucose-galactose malabsorption syndrome
    Hereditary fructose intolerance
    History of depression
    Ischaemic heart disease
    Lactose intolerance
    Occlusive peripheral vascular disorder
    Raynaud's syndrome
    Renal impairment

    Advise ability to drive/operate machinery may be affected by side effects
    Some formulations contain hydroxybenzoate
    Some formulations contain lactose
    Stop betablocker several days before clonidine if withdrawing combination
    Do not withdraw this drug suddenly
    Advise patient to avoid alcohol during treatment
    Advise contact lens wearers of possibility of reduced lacrimation
    Advise patient on possible rebound phenomena on withdrawal

    Clonidine Hydrochloride can cause bradycardia. In patients with pre-existing cardiac conduction abnormalities, arrhythmias have been observed after high doses.

    Pregnancy and Lactation


    Use clonidine with caution in pregnancy, particularly in the 1st trimester.

    The manufacturer advises not using clonidine in pregnancy, espicially during the first trimester, unless the expected benefit is thought to outweigh any possible risk to the foetus.

    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. Available reports regarding animal studies indicate no foetal malformations. Effects on foetal development were seen in one species only. Careful monitoring of mother and child is recommended.

    Schaefer (2015) states clonidine should not be used during pregnancy, however if used during the first trimester, a follow up sonography may be considered.


    Clonidine is contraindicated during breastfeeding.

    The manufacturer recommends not using clonidine during breastfeeding. Clonidine is excreted in human milk. However, there is limited information on the effects of the newborn.

    Side Effects

    Abnormal liver function tests
    Atrioventricular block
    Cardiac failure
    Decreased lacrimation
    Disturbances in accommodation
    Dry mouth
    Dryness and irritation of eyes
    Dryness of nasal mucosa
    Erectile dysfunction
    Fluid retention
    Hypersensitivity reactions
    Orthostatic hypotension
    Pain in salivary glands
    Perceptual disturbances
    Pseudo-obstruction of the large intestine
    Raynaud's phenomenon
    Reduced libido
    Restlessness (nocturnal)
    Sinus bradycardia
    Sleep disturbances


    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 ( ).

    Further Information

    Last Full Review Date: November 2018

    Reference Sources

    Drugs During Pregnancy and Lactation: Treatment Options and Risk Assessment, 3nd edition (2015) ed. Schaefer, C., Peters, P. and Miller, R. Elsevier, London.

    Summary of Product Characteristics: Clonidine 25mcg Tablets BP. Sandoz Ltd. Revised July 2016.
    Summary of Product Characteristics: Clonidine 50mcg/5ml oral solution. Thame Laboratories. Revised August 2018.

    NICE Evidence Services Available at: Last accessed: 23 November 2018

    The Welsh Medicines Information Centre (WMIC) Porphyria Information Service.
    Available at:
    Last revised: 05 May 17
    Last accessed: 23 November 2018

    The Norwegian Porphyria Centre (NAPOS).
    Available at:
    Last revised: 22 September 2018
    Last accessed: 23 November 2018

    US National Library of Medicine. Toxicology Data Network. Drugs and Lactation Database (LactMed).
    Available at:
    Clonidine Last revised: 31 August 2018
    Last accessed: 23 Novemeber 2018

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