Psychiatric Medications
Clonidine
Brand Name: Catapres
Overview
Catapres is the brand name for Clonidine. Catapres is an Alpha2-adrenergic agonist and works by stimulating a set of receptors in the brainstem that results in reduced sympathetic outflow from the central nervous system, producing a decrease in peripheral vascular resistance, heart rate, and blood pressure.
Catapres is available in tablets, or as a skin patch.
Catapres usually causes a noticeable drop in blood pressure within 30 to 60 minutes, though the full effects might not be reached for several weeks.
Why is this drug prescribed?
Catapres is FDA-approved for the treatment of essential hypertension in adults and children over the age of 12. An epidural form is approved for treatment of refractory cancer pain.
Catapres is used in children to treat ADHD. This use is not FDA approved, but it is a widely accepted use.
Catapres is used in adults to treat:
- High blood pressure
- Migraine headaches
- Menopausal syndrome
- Withdrawal syndrome due to alcohol, nicotine, or tranquilizers
- Tourette's syndrome
- Premenstrual tension
- Diabetic diarrhea
How much of this drug is typically used?
Tablets: 0.1 mg, 0.2 mg, and 0.3 mg
Once-weekly patch comes in 0.1 mg/24 hours, 0.2 mg/24 hours, and 0.3 mg /24 hours
Also comes in epidural injection form
Warnings and Precautions
Children are more sensitive to Catapres than adults and may overdose on a normal adult dose of this medication.
Catapres may impair coordination and alertness. Individuals taking Catapres should not drive or operate heavy machinery until its effects are known and do not interfere with such activities. Mental alertness is less likely to be affected when dosage is started small and gradually increased.
Suddenly discontinuing Catapres may cause withdrawal symptoms such as headache, nervousness, agitation, tremor, confusion, and a rapid rise in blood pressure.
Conditions such as polyarteritis nodosa, scleroderma, and systemic lupus erythematosus (SLE) may interfere with absorption through the skin when the skin patch is used.
For Pregnant or Nursing Mothers: During animal studies, Catapres has been found to cause certain problems, but not birth defects, in the fetus. Catapres is passed into breast milk, though it has not been shown to cause problems in the nursing infant. Pregnant and nursing women are advised not to take Catapres.
Contraindications
Catapres should Not be used for people with sinus node function impairment.
Precautions
Catapres may be used with caution in people with the following conditions:
- Heart or blood vessel disease — Catapres can make these conditions worse
- Kidney disease — dosage may need to be lowered
- Mental depression — Catapres could make this condition worse
- Raynaud's syndrome — Catapres could make this condition worse
Adverse Reactions
Catapres may cause the following reactions:
- Dizziness or lightheadedness
- Dry mouth
- Drowsiness
- Unusual tiredness or weakness
- Darkening of skin (with skin patch only)
- Impotence
- Agitation
- Dry, itching, or burning eyes
- Loss of appetite
- Loss of sex drive
- Sedation (calm)
- Changes in heartbeat
- Excessive nighttime urination
- Headache
- Mental depression
- Pounding heartbeat
- Weight gain
- For those who are not using clonidine for treatment of high blood pressure, low blood pressure may be a common side effect.
Rarely:
- Nervousness
- Sodium and water retention
- Sexual dysfunction
- Nausea or vomiting
- Constipation
Interactions with Drugs and Other Substances
Drugs or substances that may interact with Catapres include:
- Beta-blockers — such medications increase the risk of harmful side effects when Catapres treatment is discontinued suddenly
- All tricyclic antidepressants (TCAs) — these medications may decrease the effects on blood pressure
- Alcohol and other central nervous system (CNS) depressants such as antihistamines or medicine for hay fever, other allergies, or colds; sedatives, tranquilizers, or sleeping medicine; prescription pain medicine or narcotics; barbiturates; medicine for seizures; muscle relaxants; or anesthetics, including some dental anesthetics — these can increase drowsiness
Use in Child Psychiatry
Clonidine is often used third-line for treatment of ADHD in children (after stimulants and atomoxetine), and has been shown to have some benefit, although its benefit appears to be less than some other treatments for ADHD. As such, it is generally not used as first-line treatment for ADHD, unless the ADHD is associated with tics or Tourette’s syndrome. Meanwhile, clonidine is used as a first-line treatment of Tourette’s syndrome. Clonidine may be somewhat sedating, and is often given at bedtime, and may decrease hyperactivity in this manner.
Sources
- http://www.healthtouch.com/bin/EContent_HT/drugShowLfts.asp?fname=use0393.htm&title=Catapres&cid=HT
- http://www.rxmed.com/monographs/catapres.html
- http://www.healthsquare.com/newrx/CAT1072.HTM
- www.uptodate.com “Clonidine: Drug information”
- www.uptodate.com “Clonidine: Patient drug information”
- www.uptodate.com “Clonidine: Pediatric drug information”
- www.clinicalpharmacology-ip.com “Clonidine”
- Pliszka S, AACAP Work Group on Quality Issues. Practice parameter for the assessment and treatment of children and adolescents with attention-deficit/hyperactivity disorder. J Am Acad Child Adolesc Psychiatry. 2007 Jul;46(7):894-921.
- Palumbo DR, Sallee FR, Pelham WE Jr, Bukstein OG, Daviss WB, McDermott MP. Clonidine for attention-deficit/hyperactivity disorder: I. Efficacy and tolerability outcomes. J Am Acad Child Adolesc Psychiatry. 2008 Feb;47(2):180-8.
- Robertson MM. Attention deficit hyperactivity disorder, tics and Tourette's syndrome: the relationship and treatment implications. A commentary. Eur Child Adolesc Psychiatry. 2006 Feb;15(1):1-11.
- Shavitt RG, Hounie AG, Rosario Campos MC, Miguel EC. Tourette's Syndrome. Psychiatr Clin North Am. 2006 Jun;29(2):471-86.
