Question: What do hot flashes, migraine headaches, and restless legs have in common?
Answer: clonidine (generic and Catapres), a drug that's been used off-label to treat those and numerous other conditions, including attention-deficit/hyperactivity disorder (ADHD), sleep apnea, smoking cessation, Tourette's syndrome, and withdrawal from alcohol and narcotics.
If clonidine sounds like a remedy for all ills, bear in mind that it's approved by the Food and Drug Administration only to treat high blood pressure, and as an injection in combination with other medications, to ease severe cancer pain.
However, it's likely that doctors prescribe clonidine for more off-label uses than for its approved use. But the evidence for many of those off-label uses consists of only a few studies that are too small or that have other shortcomings which prevents making a clear recommendation. Where the evidence is sufficient to support its use, clonidine is generally recommended as a second-choice or additional medication when preferred treatments aren't effective or can't be used.
Available as a pill, skin patch or an injection, clonidine works by controlling certain nerve impulses. As a result, it decreases your heart rate and relaxes blood vessels so that blood can flow more easily through the body. Studies indicate that it can be useful sometimes for the following off-label indications:
ADHD. If the most effective treatments for this disorder—stimulant drugs such as methylphenidate and dextroamphetamine—don't improve your child's behavior, clonidine may help control some symptoms such as hyperactivity and impulsiveness. A 2008 randomized, placebo-controlled trial involving 122 children with ADHD found that the drug offered some benefit in the home setting but was reported to be less effective in the classroom based on parent and teacher surveys to assess the child's ADHD symptoms.
Studies suggest that clonidine may be more valuable as an adjunct medication to treat secondary ADHD symptoms and the side effects of stimulants. Those may include aggression, jittery behavior, irritability, tics, and insomnia. Clonidine is among the most commonly prescribed drugs to treat insomnia for children with ADHD, according to a survey of more than 1,200 child psychiatrists. However, the American Academy of Sleep Medicine advises first trying behavioral strategies for pediatric insomnia and using medication sparingly. Consumer Reports medical advisors urge people to avoid taking medication to treat the side effects of another drug unless that drug is essential.
Hot flashes. Estrogen-replacement therapy is the most effective treatment for this menopausal symptom, but it increases the risk of stroke, blood clots, and breast cancer. Consequently it's not recommended for many women, particularly those who have had breast cancer.
Studies suggest that clonidine modestly improves the severity and frequency of hot flashes in some women, and it's a sensible choice for those who also suffer from high blood pressure. It may also be useful for breast-cancer survivors who are taking tamoxifen, a drug that reduces the chance that cancer will recur but also induces hot flashes. However, a 2007 randomized trial by the European Society for Medical Oncology found that the antidepressant drug venlafaxine was more effective than clonidine for reducing hot flashes in breast-cancer patients.
Smoking cessation. Nicotine replacement products and the antidepressant drug bupropion sustained-release (Zyban and generic) are more effective and have fewer side effects than clonidine for smokers who are trying to kick the habit. If those first-line treatments don't work or can't be used, clonidine may be an effective alternative. A 2008 report from the U.S. Public Health Service concluded that it about doubles the odds of quitting compared with placebo.
Opioid and alcohol withdrawal. Clonidine is used as a non-narcotic alternative to methadone for reducing withdrawal symptoms in people who are trying to stop taking opiate drugs such as morphine and heroin. A review of more than 20 controlled studies found that clonidine and methadone were about equally effective, although clonidine caused more unwanted side effects.
When used in conjunction with other drugs to manage alcohol withdrawal, clonidine can reduce elevated blood pressure, increased heart rate, tremors, sweating, and anxiety.
Tourette's syndrome. Clonidine is sometimes used to treat the involuntary, repetitive movements or sounds that characterize this disorder. While dopamine-receptor-blocking drugs such as haloperidol and pimozide are more effective, they don't completely eliminate tics and they may cause unpleasant side effects. Clonidine may be helpful when used in conjunction with those medications or, if symptoms are mild, used alone. Moreover, it's a good choice for patients who have Tourette's syndrome with ADHD because it also reduces insomnia, hyperactivity, and impulsivity.
Restless legs syndrome (RLS). Although not a first-line treatment for this disorder, clonidine may be effective for a short time if the syndrome is not due to other conditions or medications. There's not enough evidence to recommend it for RLS that's due to iron deficiency or other secondary causes.