Clonidine - Dosage clonidine

Hypertension may develop early and may be followed by hypotension, bradycardia, respiratory depression, hypothermia, drowsiness, decreased or absent reflexes, weakness, irritability and miosis. The frequency of CNS depression may be higher in children than adults. Large overdoses may result in reversible cardiac conduction defects or dysrhythmias, apnea, coma and seizures. Signs and symptoms of overdose generally occur within 30 minutes to 2 hours after exposure. As little as 0.1 mg of clonidine has produced signs of toxicity in children.

If symptoms of poisoning occur following dermal exposure, remove all Clonidine Transdermal Systems. After their removal, the plasma clonidine levels will persist for about 8 hours, then decline slowly over a period of several days. Rare cases of Clonidine Transdermal System poisoning due to accidental or deliberate mouthing or ingestion of the patch have been reported, many of them involving children.

There is no specific antidote for clonidine overdosage. Ipecac syrup-induced vomiting and gastric lavage would not be expected to remove significant amounts of clonidine following dermal exposure. If the patch is ingested, whole bowel irrigation may be considered and the administration of activated charcoal and/or cathartic may be beneficial. Supportive care may include atropine sulfate for bradycardia, intravenous fluids and/or vasopressor agents for hypotension and vasodilators for hypertension. Naloxone may be a useful adjunct for the management of clonidine-induced respiratory depression, hypotension and/or coma; blood pressure should be monitored since the administration of naloxone has occasionally resulted in paradoxical hypertension. Tolazoline administration has yielded inconsistent results and is not recommended as first-line therapy. Dialysis is not likely to significantly enhance the elimination of clonidine.

The largest overdose reported to date, involved a 28-year old male who ingested 100 mg of clonidine hydrochloride powder. This patient developed hypertension followed by hypotension, bradycardia, apnea, hallucinations, semicoma, and premature ventricular contractions. The patient fully recovered after intensive treatment. Plasma clonidine levels were 60 ng/mL after 1 hour, 190 ng/mL after 1.5 hours, 370 ng/mL after 2 hours, and 120 ng/mL after 5.5 and 6.5 hours. In mice and rats, the oral LD₅₀ of clonidine is 206 and 465 mg/kg, respectively.

Apply Clonidine Transdermal System once every 7 days to a hairless area of intact skin on the upper outer arm or chest. Each new application of Clonidine Transdermal System should be on a different skin site from the previous location. If the system loosens during 7-day wearing, the adhesive cover should be applied directly over the system to ensure good adhesion. There have been rare reports of the need for patch changes prior to 7 days to maintain blood pressure control.

To initiate therapy, Clonidine Transdermal System dosage should be titrated according to individual therapeutic requirements, starting with Clonidine Transdermal System 0.1 mg/day. If after one or two weeks the desired reduction in blood pressure is not achieved, increase the dosage by adding another Clonidine Transdermal System, 0.1 mg/day or changing to a larger system. An increase in dosage above two Clonidine Transdermal System 0.3 mg/day is usually not associated with additional efficacy.

When substituting Clonidine Transdermal System for oral clonidine or for other antihypertensive drugs, physicians should be aware that the antihypertensive effect of Clonidine Transdermal System may not commence until 2 to 3 days after initial application. Therefore, gradual reduction of prior drug dosage is advised. Some or all previous antihypertensive treatment may have to be continued, particularly in patients with more severe forms of hypertension.

Patients with renal impairment may benefit from a lower initial dose. Patients should be carefully monitored. Since only a minimal amount of clonidine is removed during routine hemodialysis, there is no need to give supplemental clonidine following dialysis.

Clonidine Transdermal System, USP, 0.1 mg/day, Clonidine Transdermal System, USP, 0.2 mg/day and Clonidine Transdermal System, USP, 0.3 mg/day are supplied as 4 pouched systems and 4 adhesive covers per carton. See chart below.

Store at 20° to 25°C (68° to 77°F). [See USP Controlled Room Temperature.]

Address medical inquiries to: 1-877-446-3679 (1-877-4-INFO-RX)

Mylan Pharmaceuticals Inc.
Morgantown, WV 26505 U.S.A.

REVISED JANUARY 2013
CTS:R13