Clonidine is an alpha-2 adrenergic receptor agonist used to treat hypertension. It works by stimulating alpha-2 receptors in the brain to inhibit the release of norepinephrine, reducing peripheral vascular resistance and lowering blood pressure. Common side effects include dizziness, dry mouth, and sedation. Clonidine can also be used to treat migraines, menopausal hot flashes, and opioid withdrawal symptoms. It has drug interactions with aspirin, atenolol, and clomipramine that can increase side effects or toxicity. Clonidine is pregnancy category C and may harm the fetus or pass into breastmilk.

1. BY
ABBAS FADHIL
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2. Clonidine. Category adrenergic α2 receptor.
The treatment of hypertension.
(trade names_Catapres,Kapvay,Nexiclon,Clophelin)
Formula
C9H9Cl2N3
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3. The Alpha2 Adrenergic Receptor is an inhibitory G-
protien coupled receptor that binds norepinephrine and is
present in both the CNS and sympathetic arm of the ANS.
Within sympathetic fibers, Alpha2 receptors are uniquely
found on the presynaptic terminals of postganglionic.
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4. presynaptic
postsynaptic
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5. Clonidine treats high blood pressure by stimulating α2
receptors in the brain, thus inhibiting the release of
norepinephrine (NE). And then decreases peripheral vascular
resistance, will become vasodilation and the pressure will
decrease. It has specificity towards the presynaptic α2
receptors in the vasomotor center in the brainstem.
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6. The α-2 receptors constitute a family of G-protein–
coupled receptors with 3 pharmacological subtypes, α-
2A, α-2B, and α-2C.
The α-2A and -2C subtypes are found mainly in the
central nervous system. Stimulation of these receptor
subtypes may be responsible for sedation, analgesia.
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8. Bioavailability: Immediate release (75-85%)
Protein bound: 20-40%
Duration: 6-10 hr.
Metabolism in Liver.
Elimination Half-life: 12-16 hr.
Excretion: Urine.
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9. 1.Hypertension
2.severe dysmenorrhea
3.vascular migraine headaches
4.treatment of alcohol withdrawal used in
conjunction with benzodiazepines.
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10. 5. attention-deficit hyperactivity disorder
(ADHD)
6. Restless Legs Syndrome
7. Tourette's Syndrome
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11. 8-Epidural clonidine analgesia for cancer pain.
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12. 1.ORAL TABLET
 0.1mg
 0.2mg
 0.3mg
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• 2 times a day (morning
and bedtime) to 0.1 mg

13. 2.injectable solution:-
 100mcg/ml
 500mcg/ml
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14. 3.Transdermal
 patch,
 0.1mg/day
 0.2mg/day
 0.3mg/day
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• Change every
7 days

15. Very common side effects is:-
• Dizziness
• Skin reactions (if given transdermally)
• Orthostatic
• Somnolence (dose-dependent)
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16. Common side effects:-
• Constipation
• vomiting
• Rash
• Weight gain/loss
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17. Rare side effects:-
• Hallucination
• Pruritus
• Nasal dryness
• Alopecia
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18. Pregnancy Category C.
Clonidine may be pass through the barrier of placenta then
enter blood circulation of fetus and cause decrease blood
pressure of the fetus with decrease heart rate. May be die.
Clonidine can pass into breast milk and may harm the
baby; caution is warranted in women who are pregnant,
planning to become pregnant, or are breastfeeding.
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20. Drug interactions may change how your
medications work or increase your risk for serious
side effects. Do not start, stop, or change the dosage
of any medicines without your doctor's approval.
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21.  Aspirin:-
Using aspirin with clonidine may increase side effects such as
dizziness, drowsiness, confusion, and difficulty concentrating.
 Atenolol:-
clonidine, atenolol. Either increases toxicity of the other by
unspecified interaction mechanism. Avoid or Use Alternate
Drug. Can increase risk of bradycardia.
Clomipramine:-
This combination may cause vomiting, sweating, flushing,
dizziness, headache or heart palpitations.
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22. Ginseng: Clonidine is used in the treatment of hypertension.
Interaction of clonidine with ginseng may affect the action of
the drug as ginseng can increase the blood pressure.
Other Herbs: Saw palmetto, hawthorn, goldenseal, licorice
and yohimbe may increase the blood pressure and interfere
with the effect of clonidine.
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23. The End
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2. www.uspharmacist.com
3. http://www.pathwaymedicine.org
4. www.webmd.com
5. www.medscape.com
6. www.drugbank.ca
7. http://www.medicalook.com
8. www.wikipedia.org
9. www.healthline.com
10.www.medindia.net