What are the parameters for Clonidine (Clonidine hydrochloride)?

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Last updated: March 10, 2025 • View editorial policy

From the Guidelines

Clonidine should be dosed at 0.1-0.8 mg orally two times daily, with careful consideration of its potential for significant CNS adverse effects, especially in older adults, as noted in the 2018 guideline for the prevention, detection, evaluation, and management of high blood pressure in adults 1. The dosing of clonidine can vary based on the specific condition being treated, such as hypertension or ADHD.

  • For hypertension, the dose can be started at 0.1 mg twice daily and titrated upward every 1-2 weeks based on blood pressure response, with a maximum daily dose of 0.8 mg, as indicated in the guideline 1.
  • For ADHD in children, dosing usually begins at 0.1 mg/day and may increase by 0.1 mg weekly to a maximum of 0.4 mg/day divided into 2-4 doses, according to the evidence-based pharmacological treatment options for ADHD in children and adolescents 2. When monitoring clonidine therapy, it is essential to check blood pressure and heart rate regularly, as the medication can cause hypotension and bradycardia.
  • Common side effects include dry mouth, sedation, dizziness, and constipation.
  • Never abruptly discontinue clonidine, as this can cause rebound hypertension; instead, taper gradually over 1-2 weeks, as warned in the guideline 1. Clonidine works by stimulating alpha-2 adrenergic receptors in the brain, reducing sympathetic outflow and decreasing peripheral vascular resistance, which explains its antihypertensive effects, as described in the pharmacological treatment options for ADHD in children and adolescents 2.
  • For off-label uses like opioid withdrawal, ADHD, or pain management, dosing may vary, so it is crucial to adjust based on clinical response and tolerability.

From the FDA Drug Label

CLINICAL PHARMACOLOGY Clonidine stimulates alpha-adrenoreceptors in the brain stem. This action results in reduced sympathetic outflow from the central nervous system and in decreases in peripheral resistance, renal vascular resistance, heart rate, and blood pressure. The pharmacokinetics of clonidine is dose-proportional in the range of 100 to 600 mcg. The absolute bioavailability of clonidine on oral administration is 70% to 80% Peak plasma clonidine levels are attained in approximately 1 to 3 hours. Following intravenous administration, clonidine displays biphasic disposition with a distribution half-life of about 20 minutes and an elimination half-life ranging from 12 to 16 hours. The antihypertensive effect is reached at plasma concentrations between about 0. 2 and 2.0 ng/mL in patients with normal excretory function.

The parameters for Clonidine (Clonidine hydrochloride) are:

  • Dose-proportional range: 100 to 600 mcg
  • Absolute bioavailability: 70% to 80%
  • Peak plasma levels: attained in approximately 1 to 3 hours
  • Distribution half-life: about 20 minutes
  • Elimination half-life: ranging from 12 to 16 hours
  • Therapeutic plasma concentrations: between about 0.2 and 2.0 ng/mL 3

From the Research

Parameters for Clonidine (Clonidine hydrochloride)

The parameters for Clonidine (Clonidine hydrochloride) are as follows:

  • Initial oral dose: 0.1 to 0.2 mg 4, or 0.2 mg 5, 6
  • Hourly doses: 0.05 or 0.1 mg 4, or 0.1 mg 6
  • Total dose: up to 0.7 mg 4, or up to 0.8 mg 5, 6
  • Dosage frequency: hourly 4, 5, 6, or twice daily 7
  • Dosage form: oral 4, 5, 6, 7, or transdermal 8
  • Target blood pressure: goal blood pressure that does not reduce perfusion to critical organs 4, or diastolic blood pressure less than or equal to 90 mmHg 7

Side Effects

  • Minimal side effects 5, 6
  • Dry mouth 7
  • Cerebral infarct (in one patient) 5

Patient Monitoring

  • Immediate outpatient follow-up within 24 hours is mandatory in all patients who are not hospitalized 4
  • Close observation, intravenous lines, and hospitalization may not be required 4

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.