YSP Clonidine Special Precautions

Special care should be exercised in treating patients who have a history of depression or who have advanced cerebrovascular disease. Reduction of blood pressure in the latter circumstances may itself cause mental changes. Concurrent administration of tricyclic antidepressants may require adjustment of Clonidine dosage.
Although a transient rise in blood sugar has been noted occasionally in humans treated with Clonidine, which may be due to a pharmacologic alpha-adrenomimetic effect of the drug, no case of induced diabetes mellitus due to Clonidine has been reported. Patients with clinical diabetes mellitus should be watched for a possible increase in their requirements of anti-diabetic therapy.
Clonidine should be used with caution in patients with mild to moderate bradyarrhythmia such as low sinus rhythm, with disorders of cerebral or peripheral perfusion, polyneuropathy, and constipation.
No therapeutic effect of Clonidine can be expected in the treatment of hypertension caused by phaeochromocytoma.
Since Clonidine and its metabolites are extensively excreted in the urine, careful adjustment of dosage is required in patients with renal insufficiency.
As with other anti-hypertensives, treatment with Clonidine should be monitored particularly carefully in patients with heart failure or severe coronary heart disease.
Termination of oral therapy should be gradual (e.g. over more than 7 days). Sudden cessation of antihypertensive therapy is known to be associated in some instances with rebound hypertension which in some cases may be severe. This may occur with Clonidine, particularly in patients receiving more than the maximum recommended dose of 900 micrograms per day.
Following sudden discontinuation of Clonidine after prolonged treatment with high doses, restlessness, palpitations, rapid rise in blood pressure, nervousness, tremor, headache, or nausea have been reported.
An excessive rise in blood pressure following discontinuation of Clonidine therapy can be reversed by intravenous phentolamine.
If long-term treatment with a β-blocker needs to be interrupted, the β-blocker should be gradually phased out first, then clonidine.
Patients who wear contact lenses should be warned that treatment with Clonidine may cause decreased lacrimation.
Patients with the rare hereditary conditions of galactose intolerance e.g. galactosaemia, should not take this medicine.
Anaesthesia: Abrupt withdrawal of Clonidine is undesirable. Limited evidence suggests that it is unnecessary to withdraw Clonidine before anaesthesia and that maintenance of therapy is preferable to abrupt withdrawal. In the peri-operative period, Clonidine can, where necessary, be administered parenterally until oral therapy is resumed.
Where therapy with Clonidine is to be suspended before operation, withdrawal should be gradual (i.e. over more than 7 days) and monitored by regular observation of blood pressure.
Effects on laboratory tests: No data available.
Effects on Ability to Drive and Use Machines: No studies on the effects on the ability to drive and use machines have been performed.
However, patients should be advised that they may experience undesirable effects such as dizziness, sedation, and accommodation disorder during treatment with Clonidine. Therefore, caution should be recommended when driving a car or operating machinery. If patients experience the previously mentioned side effects, they should avoid potentially hazardous tasks such as driving or operating machinery.
Use in Children: The use and the safety of clonidine in children and adolescents has little supporting evidence in randomised controlled trials and therefore cannot be recommended for use in this population.
In particular, when clonidine is used off-label concomitantly with methylphenidate in children with ADHD, serious adverse reactions, including death, have been observed. Therefore, clonidine in this combination is not recommended.
Use in the Elderly: No data available.