Clonidine Flashcards
Please note that the drug card information is for Educational Use ONLY, and the source is from Carrie Bowman's glossary of drug cards permitted by use of Georgetown NAP students. No permission is given to use these cards for anything other than as a study resource for our program.
What is the trade name for clonidine?
Catapres
What is the formal drug classification of clonidine?
partial central alpha-2 adrenergic agonist
What are the clinical uses of Clonidine?
- hypertension
- drug withdrawal symptoms
- analgesia in acute and chronic pain states (use limited due the adverse effects of postural hypotension and sedation)
- Preanesthetic drug
- used to decrease myocardial ischemia, infarction, and mortality following CV surgery
- used in diagnosis of pheochromocytoma
- controls shivering
- used as a neuroaxial analgesic, which prolongs the anesthesia effect when mixed with local anesthetics
What are the uses of clonidine for preanesthesia?
1) Blunts the SNS response to direct laryngoscopy for intubation
2) Decreases intraoperative lability of blood pressure and heart rate
3) Decreases plasma catecholamine concentrations
4) Dramatically decreases anesthetic requirements for inhaled and injected drugs
What is the MOA for Clonidine?
Selectively avtivates alpha-2 adrenergic receptors and thereby inhibits sympathetic outflow from the medulla, which then causes a decrease in heart rate, contractility, and vasomotor tone
What is the MOA of Clonidine for analgesia purposes?
the alpha-2 adrenergic receptors found in the dorsal horn of the spinal cord produces an anti-nocioceptive state by inhibiting the release of spinal substance P and nocioceptive neuron firing produced by painful stimuli
How does Clonidine treat drug withdrawal symptoms?
by blocking the sympathetic hyperactivity and to a certain extent the GI hyperactivity seen in withdrawal
The alpha-2 receptors inhibit the stimulation of noradrenergic neurons in the brain and cholinergic neurons in the gut associated with opioid withdrawal, and alpha-2 agonists partially block opioid withdrawal symptoms
How does Clonidine stop shivering?
Alpha2B receptors stop shivering by inhibiting central thermoregulatory control, which decrease the vasoconstriction and shivering thresholds
What electrolyte channel dose Clonidine affect? Whats this cause?
Affects the function of the potassium channel in the CNS, making the cell hyperpolarized, which leads to the decrease anesthetic requirement
If given orally how is clonidine absorbed?
rapidly absorbed when given orally
What is the onset of action of PO Clonidine?
0.5-1 hour PO
When does Clonidine produce peak plasma concentrations when given PO?
60-90 minutes
What is the DOA of PO Clonidine?
8 hours PO
How is Clonidine metabolized and eliminated?
- 50% of the drug is metabolized in the liver
- 50% excreted unchanged in the urine
What is the elimination 1/2 time of Clonidine?
9-12 hours