klonidiini

Clonidine, known in Finnish as klonidiini, is a centrally acting antihypertensive medication that reduces sympathetic outflow from the brain. It is an alpha-2 adrenergic receptor agonist, and by stimulating receptors in the brainstem, it lowers peripheral vascular resistance and heart rate, thereby reducing blood pressure.

Clonidine is approved for the treatment of hypertension and has several off-label uses. It is sometimes used as an adjunct to stimulant medications for attention-deficit hyperactivity disorder in children when symptoms persist. It is also employed to alleviate withdrawal symptoms from opioids, nicotine, and alcohol, and has been used in Tourette syndrome to reduce tics.

Clonidine is available as oral tablets and as a transdermal patch. Oral tablets commonly contain 0.1 mg or 0.2 mg; patches provide a continuous dose over 24 hours. Onset of blood pressure effects with oral dosing occurs within one hour, while the patch achieves a steadier effect over several days. The drug is metabolized in the liver and eliminated by the kidneys. The usual half-life is about 12 to 16 hours in adults, but can be longer in the elderly.

Common adverse effects include sedation, drowsiness, dry mouth, dizziness, and constipation. Cardiovascular effects such as bradycardia or orthostatic hypotension can occur. Abrupt discontinuation may trigger rebound hypertension, tachycardia, and agitation; gradual tapering is advised. Clonidine can enhance the effects of other sedatives and antihypertensives, and care is required in patients with severe heart block or low blood pressure. Use in pregnancy should be carefully considered with a clinician.