Examples

Clonidine is available by prescription only in pill or patch form. Use of clonidine for treating hot flashes is an unlabeled use, although it is considered a reasonable treatment option by health professionals and is supported by limited research.

How It Works

Clonidine is a blood pressure medication that relaxes the smooth muscle of blood vessels, causing them to widen, or dilate. This reduces the pressure of blood flow through the artery. Clonidine's effect on hot flashes is not well understood.

Why It Is Used

Clonidine can be used to treat hot flashes. Because it is a nonhormonal treatment, women with a history of breast cancer can use it without increasing the risk of further cancer cell growth (as in the case of estrogen treatment).

How Well It Works

Two randomized controlled trials have shown that clonidine can reduce the number of hot flashes suffered per day and can slightly reduce the length and severity of hot flashes. Clonidine treatment works for some women and not at all for others. Those taking a higher dose have reported more hot flash relief than those on a lower dose.^{1, 2}

Long-term treatment beyond a couple of months has yet to be researched, but researchers speculate that positive effects would continue over time.²

If you have high blood pressure and hot flashes, clonidine may be an effective choice for both problems.

Side Effects

Possible side effects of clonidine include:

• Drowsiness, fatigue.
• Dry mouth.
• Difficulty sleeping.
• Dizziness.
• Nausea.

Clonidine lowers blood pressure, so your blood pressure is monitored while you are taking this medication. With low blood pressure, sitting or standing up quickly may make you dizzy (called postural or orthostatic hypotension).

The clonidine patch may cause skin irritation.

See Drug Reference for a full list of side effects. (Drug Reference is not available in all systems.)

What To Think About

One study has reported that women taking clonidine at bedtime reported more trouble sleeping than those taking placebo, but no other side effects were observed.²

The clonidine patch should be changed weekly.

Do not suddenly stop taking clonidine. To stop clonidine use, slowly decrease your dose over 2 to 4 days to prevent nervousness, agitation, headache, confusion, and tremor along with a sudden rise in blood pressure (rebound hypertension).

Complete the new medication information form (PDF)(What is a PDF document?) to help you understand this medication.

Citations

1. Rymer J, Morris EP (2000). Extracts from "Clinical Evidence": Menopausal symptoms. BMJ, 321(7275): 1516–1519.

2. Pandya KJ, et al. (2000). Oral clonidine in postmenopausal patients with breast cancer experiencing tamoxifen-induced hot flashes: A University of Rochester Cancer Center Community Clinical Oncology Program study. Annals of Internal Medicine, 132(10): 788–793.