03/04/2009 19:43

Clonidine hydrochloride

Brand Name:

Antihypertensives: Apo-Clonidine (CAN), Catapres, Catapres-TTS (transdermal preparation), Dixarit (CAN), Nu-Clonidine (CAN)

Analgesic: Duraclon

Pregnancy Category C

Drug classes: Antihypertensive, Sympatholytic, centrally acting, Central analgesic


Therapeutic actions

Stimulates CNS alpha2-adrenergic receptors, inhibits sympathetic cardioaccelerator and vasoconstrictor centers, and decreases sympathetic outflow from the CNS.



· Hypertension, used alone or as part of combination therapy

· Treatment of severe pain in cancer patients in combination with opiates; epidural more effective with neuropathic pain (Duraclon)

· Unlabeled uses: Tourette's syndrome; migraine, decreases severity and frequency; menopausal flushing, decreases severity and frequency of episodes; chronic methadone detoxification; rapid opiate detoxification (in doses up to 17 mcg/kg/day); alcohol and benzodiazepine withdrawal treatment; management of hypertensive "urgencies"; (oral clonidine "loading" is used; initial dose of 0.2 mg then 0.1 mg every hour until a dose of 0.7 mg is reached or until BP is controlled)



· Contraindicated with hypersensitivity to clonidine or any adhesive layer components of the transdermal system.


Adverse effects

Oral therapy

Drowsiness, sedation, dizziness, headache, fatigue that tend to diminish within 4–6 wk, dreams, nightmares, insomnia, hallucinations, delirium, nervousness, restlessness, anxiety, depression, retinal degeneration

CHF, orthostatic hypotension, palpitations, tachycardia, bradycardia, Raynaud's phenomenon, ECG abnormalities manifested as Wenckebach period or ventricular trigeminy

Rash, angioneurotic edema, hives, urticaria, hair thinning and alopecia, pruritus, dryness, itching or burning of the eyes, pallor

Dry mouth, constipation, anorexia, malaise, nausea, vomiting, parotid pain, parotitis, mild transient abnormalities in liver function tests

Impotence, decreased sexual activity, diminished libido, nocturia, difficulty in micturition, urinary retention

Weight gain, transient elevation of blood glucose or serum creatine phosphokinase, gynecomastia, weakness, muscle or joint pain, cramps of the lower limbs, dryness of the nasal mucosa, fever

Transdermal system

Drowsiness, fatigue, headache, lethargy, sedation, insomnia, nervousness

Dry mouth, constipation, nausea, change in taste, dry throat

Impotence, sexual dysfunction

Transient localized skin reactions, pruritus, erythema, allergic contact sensitization and contact dermatitis, localized vesiculation, hyperpigmentation, edema, excoriation, burning, papules, throbbing, blanching, generalized macular rash



· Decreased antihypertensive effects with TCAs (imipramine)

· Paradoxical hypertension with propranolol; also greater withdrawal hypertension when abruptly discontinued and patient is taking beta-adrenergic blocking agents



Nursing considerations


Name confusion has been reported between clonidine and Klonopin (clonazepam); use caution.


· Do not discontinue abruptly; discontinue therapy by reducing the dosage gradually over 2–4 days to avoid rebound hypertension, tachycardia, flushing, nausea, vomiting, cardiac arrhythmias (hypertensive encephalopathy and death have occurred after abrupt cessation of clonidine).

· Do not discontinue prior to surgery; monitor BP carefully during surgery; have other BP-controlling drugs on standby.

· Store epidural injection at room temperature; discard any unused portions.

· Reevaluate therapy if clonidine tolerance occurs; giving concomitant diuretic increases the antihypertensive efficacy of clonidine.

· Monitor BP carefully when discontinuing clonidine; hypertension usually returns within 48 hr.

· Assess compliance with drug regimen in a supportive manner with pill counts, or other methods.