Buy Clonidine (Catapres) Cas 4205-90-7

Clonidine, sold under the brand name Catapres and Kapvay, among others, is an α₂-adrenergic receptor agonist, hypotensive and anxiolytic drug used to treat high blood pressure, attention deficit hyperactivity disorder, perioperative pain, drug withdrawal (e.g., alcohol, opioids, or nicotine), and menopausal flushing.^[16][17][18] Clonidine is often prescribed off-label for tics. It is used orally (by mouth), by injection, or as a transdermal skin patch.^[18] Onset of action is typically within an hour with the effects on blood pressure lasting for up to eight hours.^[18] Xylazine is a structural analog of clonidine.^[19]

Common side effects include dry mouth, dizziness, headaches, hypotension, and sleepiness.^[18] Severe side effects may include hallucinations, heart arrhythmias, and confusion.^[20] If rapidly stopped, withdrawal effects may occur, such as a dangerous rise in blood pressure.^[18] Use during pregnancy or breastfeeding is not recommended.^[20] Clonidine lowers blood pressure by stimulating α₂-adrenergic receptors and imidazoline receptors in the brain, which results in relaxation of many arteries.^[16][18]

Clonidine was patented in 1961 and came into medical use in 1966.^[21][22][23] It is available as a generic medication.^[18] In 2023, it was the 82nd most commonly prescribed medication in the United States, with more than 8 million prescriptions.^[24][25]

Clonidine is used to treat high blood pressure, attention deficit hyperactivity disorder (ADHD); drug withdrawal, including from (alcohol, opioids, and/or nicotine); menopausal flushing, diarrhea, and certain pain conditions.^{[6][10][8][18]}

Hypertension is a chronic elevation of arterial blood pressure that increases the risk of cardiovascular disease and organ damage.^[26] Many people with essential hypertension experience increased sympathetic nervous system activity, in addition to renin–angiotensin–aldosterone system activation.^[26] Clonidine is a non-selective α₂ adrenoreceptor and imidazoline receptor agonist that reduces sympathetic nervous system output from the brainstem, which lowers peripheral vascular resistance, heart rate and plasma renin activity, thereby reducing systolic and diastolic blood pressure as a consequence.^[16]

Meta-analyses of randomized controlled trials in arterial hypertension have found that clonidine is an effective antihypertensive that leads to greater reductions in systolic and diastolic blood pressure than placebo.^[27][28] A 2024 network meta-analysis of imidazoline receptor agonists (i.e., moxonidine and clonidine) reported that this drug class produced ambulatory blood pressure reductions that were close in magnitude to those of commonly used first-line antihypertensive drug classes, but with higher odds of adverse effects such as dry mouth and sedation, especially with clonidine.^[28] Hypertension Canada’s 2020 clinical practice guideline on resistant hypertension similarly notes that clonidine significantly lowers blood pressure in clinical trials, though it is considered a second-line therapy due to its potential for side effects.^[29] A 2025 review of randomized and observational studies on transdermal clonidine reported that once-weekly patch formulations achieve blood pressure reductions similar to beta blockers, calcium channel blockers and diuretics, while reducing the risk of withdrawal-related rebound hypertension compared with oral clonidine.^[30]

Clonidine is not considered a first-line treatment for hypertension due to its propensity to cause sedation and xerostomia compared with other antihypertensive medications (e.g., angiotensin-converting enzyme inhibitors).^[31] When used for blood pressure control, clonidine is typically reserved for hypertensive emergencies rather than routine management hypertension, but it is considered appropriate for treating resistant hypertension.^[31]