clonidine

• Clonidine (Catapres, Catapres-TTS) is an oral and topical (applied to the skin) medication prescribed by a doctor for the treatment of high blood pressure (hypertension). It acts by stimulating receptors on nerves in the brain that reduces the transmission of messages from nerves in the brain to nerves in other areas of the body. As a result, it slows the heart rate and reduces blood pressure.
• The FDA approved clonidine in September 1974.

What brand names are available for clonidine?

• Catapres, Catapres-TTS, and Kapvay are the brand names for this drug available in the U.S. to treat high blood pressure.
• The brand Jenloga has been discontinued in the U.S.

Is clonidine available as a generic drug?

• There are generic versions of the tablets and patches.

Do I need a prescription for clonidine?

• Yes, a prescription by a doctor or health care professional is necessary for this drug.

• Clonidine is approved for the treatment of high blood pressure. It may be used alone or combined with other drugs used for the treatment of high blood pressure.
• Clonidine is also used off-label for the treatment of alcohol withdrawal, smoking cessation, restless leg syndrome, Tourette’s syndrome, and opioid withdrawal.

Non-FDA approved (off-label) uses for this medication include the treatment of:

• Symptoms of narcotic withdrawal
• Nicotine withdrawal
• Diabetes-associated diarrhea
• Diabetic neuropathy (nerve damage)
• Hot flashes associated with menopause
• Alcohol withdrawal
• Smoking cessation
• Restless leg syndrome
• Tourette’s syndrome

It also can be used as an adjunct to manage severe cancer-related pain.

The most common side effects are:

• Tiredness
• Lethargy
• Drowsiness
• Constipation
• Dry mouth
• Headache
• Dizziness
• Fatigue
• Weakness

Other side effects include:

• Skin redness
• Itching
• Impotence
• Darkening of skin
• Decreased sexual desire
• Ejaculatory dysfunction

Possible serious side effects include:

• Severe rebound high blood pressure
• Severe low blood pressure
• Slow heart rate
• Withdrawal symptoms
• Depression
• Angioedema
• Severe allergic reactions
• Slow heart rate
• Fainting
• Abnormal heart conduction

Severe rebound hypertension can occur following withdrawal from clonidine. This reaction is more likely to occur if clonidine is stopped suddenly (without a gradual dose reduction).

Symptoms of severe rebound high blood pressure can include:

• Increased salivation
• Nervousness
• Headache
• Heart palpitations
• Agitation
• Anxiety
• Sweating
• Nausea
• Muscle pain
• Abdominal pain

Slowly reducing the dose of this medication over several days will prevent these symptoms.

• The usual oral adult dose is 0.1–0.3 mg twice daily.
• The maximum oral dose is 2.4 mg daily.
• Topical patches should be applied to an area of hairless skin on the upper arm or torso, once every 7 days.
• When applying a new topical patch, a different area of skin should be used.

This drug can increase the sedating effects of other medications that cause sedation. Such drugs include:

• Narcotic pain relievers
• Barbiturates
• Sedatives such as alprazolam (Xanax) and clonazepam (Klonopin)
• Ethanol

Tricyclic antidepressants, for example, amitriptyline (Elavil, Endep), imipramine (Tofranil), desipramine (Norpramin), and clomipramine (Anafranil), can block blood pressure lowering effects of Catapres. This may cause blood pressure to rise.

Since this drug can reduce heart rate, it should be used cautiously in persons who are receiving any other medication that lowers heart rate such as beta-blockers, for example:

• atenolol (Tenormin)
• metoprolol (Lopressor)
• propranolol (Inderal)
• digoxin (Lanoxin)
• diltiazem (Cardizem)
• verapamil (Calan Covera HS)

Abnormal heart rhythms can occur with the combination of clonidine and verapamil.

Cyclosporine (Sandimmune, Neoral) concentrations in the blood can increase when clonidine is begun. This interaction could result in kidney damage from the increased levels of cyclosporine.

Nonsteroidal anti-inflammatory drugs (NSAIDs), for example, ibuprofen (Motrin, Advil), naproxen (Naprosyn, Aleve), and nabumetone (Relafen) can reduce the antihypertensive effects of clonidine.

Cocaine, pseudoephedrine, phenylephrine, and phenylpropanolamine can also reverse clonidine's blood pressure-lowering effects.

• There are no adequate studies of this drug during pregnancy
• It is excreted into breast milk and potentially could cause adverse effects in the infant.

• Tablets (immediate release): 0.1, 0.2, and 0.3 mg.
• Transdermal patches: 0.1, 0.2, and 0.3 mg delivered over 24 hours.

• Tablets and patches should be kept at room temperature, 15 C - 30 C (59 F - 86 F).