Clonidine

(kloh-nuh-deen)

Trade/other name(s): Duraclon

Why would this drug be used?

Clonidine is used as a non-opioid pain reliever. It belongs to a general group of drugs called anti-adrenergic agents. The drug is especially useful for neuropathic pain (numbness, tingling, burning, shooting, or electric-shock-like pain.)

How does this drug work?

Clonidine is given into the epidural space around the spinal cord where it stimulates adrenergic receptors. When given together into this space with opioid analgesics, such as morphine, it increases the pain-relieving effect.

Before taking this medicine

Tell your doctor…

• If you are allergic to anything, including medicines, dyes, additives, or foods.
• If you have any bleeding problems, or if you are taking blood thinners. Using this medicine might cause bleeding around the spinal cord.
• If you have high blood pressure, or heart or blood vessel disease. Clonidine may make these problems worse.
• If you have kidney disease. Clonidine may build up in the body and cause more ill effects.
• If you are pregnant, trying to get pregnant, or if there is any chance of pregnancy. There may be an increased risk of harm to the fetus if a woman takes this drug during pregnancy.
• If you are breast-feeding. Large amounts of this drug pass into breast milk and can possibly harm the baby.
• About any other prescription or over-the-counter medicines you are taking, including vitamins and herbs. In fact, keeping a written list of each of these medicines (including the doses of each and when you take them) with you in case of emergency may help prevent complications if you get sick.

Interactions with other drugs

Heart or blood pressure medicines called beta blockers, such as atenolol, metoprolol, propranolol, or timolol may increase the risk of harm when clonidine is stopped. Beta blockers are usually stopped a few days before clonidine is tapered off.

Taking digoxin or calcium channel blockers (another type of blood pressure medicine) along with clonidine may increase risk of ill effects on the heart.

Medicines that slow down the brain or nervous system, such as other pain relievers, tranquilizers, sedatives, sleeping pills, antidepressants, muscle relaxers, antihistamines, phenothiazines, anesthetic medicines, and alcohol can cause worse side effects, such as slowed breathing, low blood pressure, and extreme sleepiness if taken with clonidine.

Tricyclic antidepressants, such as amitriptylene, nortriptylene, desiprimine, and doxepin, may change the effect of clonidine on blood pressure.

Check with your doctor, nurse, or pharmacist about whether other medicines, vitamins, herbs, and supplements can cause problems with this medicine.

Interactions with foods

Alcohol can worsen side effects, including sleepiness and low blood pressure. Otherwise, no serious interactions with foods are known at this time. Check with your doctor, nurse, or pharmacist about whether foods may be a problem.

Tell all the doctors, dentists, nurses, and pharmacists you visit that you are taking this drug.

How is this drug taken or given?

Clonidine is given as a continuous infusion into the space around the spine through an epidural catheter (thin tube) along with other medicines to stop pain. The catheter will stay in place as long as you are receiving this medicine into the spine. The dose depends on the type of pain and the relief you get. Clonidine is given by other routes (such as by mouth) for other purposes.

Precautions

This medicine can cause drowsiness and lightheadedness. Do not drive, operate machinery, or perform other activities that require alertness until you know how you react to this medicine.

Clonidine can make you feel dizzy or faint, and increase your risk of falling. Be careful getting up, changing position, or walking. Start slowly and hold onto something or someone to hold you steady. Have a responsible adult with you until you know how the medicine will affect you and that you can take care of yourself.

Since clonidine affects the central nervous system, it is important not to take other drugs or substances that slow down the brain or nervous system such as alcohol, sedatives, muscle relaxers, and sleeping pills unless your doctor tells you to do so.

You will have your blood pressure taken frequently during the first 2 days of using the drug, as clonidine can cause your blood pressure to drop. Tell your doctor or nurse if you feel different, or if you get dizzy or faint when you stand or sit up.

Do not stop this medicine before you talk with your doctor. Suddenly stopping the drug can cause anxiety, nervousness, headache, tremors, and a quick rise in blood pressure. The doctor will usually lower the drug dose gradually over 2 to 4 days. Call the doctor right away if you think the clonidine infusion has stopped, or if you notice headache, shaking or trembling, pounding heart, nervousness, agitation, or headache.

Call your doctor or nurse right away if you notice any problems with the epidural catheter, the pump, the tubing, or the skin in the area where the catheter goes into your body.

Call your doctor if you notice fever, or if you see pus, redness, or drainage around the catheter.

Most cancer pain can be controlled. Keep your doctor or nurse informed about how well your pain medicines are working and any side effects you are having. Your cancer team may need to adjust your medicines several times before they find the medicines that work best for you.

Possible side effects

You will probably not have most of the following side effects, but if you have any talk to your doctor or nurse. They can help you understand the side effects and cope with them.

Common

• low blood pressure, especially when first sitting or standing up, which can make you feel dizzy or faint*
• slow heart rate
• anxiety
• confusion*
• drowsiness
• fainting*

Less common

• fast heartbeat
• pain in chest
• shallow or slow breathing
• nausea
• dry mouth
• fever*
• if drug is stopped suddenly, increased blood pressure, nervousness, agitation, headache, and tremors*

Rare

• vomiting
• constipation
• shortness of breath
• fever*
• weakness
• low sex drive
• depression
• impotence
• hallucinations (seeing or hearing things that aren't there)
• if drug is stopped suddenly, stroke, brain damage, or death in rare cases*

*See "Precautions" section for more detailed information

There are other side effects not listed above that can also occur in some patients. Tell your doctor or nurse if you develop these or any other problems.

FDA approval

Yes – first approved in 1996 for use in pain control.

Disclaimer: This information does not cover all possible uses, actions, precautions, side effects, or interactions. It is not intended as medical advice, and should not be relied upon as a substitute for talking with your doctor, who is familiar with your medical needs.