Clonidine Side Effects: How Do They Manifest?

Last Updated: March 16, 2020

Authored by Isaak Stotts, LP

There is the potential for a multitude of clonidine side effects, especially when misused for the long-term. While many of Catapres side effects pass with time, others will require immediate medical attention.

What Are The Most Common Side Effects Of Clonidine?

The most common side effects of Catapres include the following:

  • Dry mouth and dry eyes
  • Dizziness
  • Tiredness
  • Stomach upset or pain
  • Sedation
  • Constipation
  • Headache
  • Upper respiratory tract infection
  • Feeling irritable
  • Trouble sleeping
  • Nightmares

One of the clonidine side effects is the inhibition of the release of norepinephrine (NE). This decreases secretions from the salivary gland, causing dry mouth. It also decreases sympathetic tone, which explains constipation. Catapres’ sedative effect on users in the short-term causes drowsiness. Depression is also common.

rare side effects of clonidine

Rare Side Effects Of Catapres

The uncommon Catapres side effects may manifest in the following ways:

  • bradycardia
  • blurred vision
  • hair loss or thinning of the hair
  • pale skin
  • muscle ache
  • joint pain
  • leg cramps
  • swelling of the breasts
  • loss of interest in sexual intercourse
  • inability to have or keep an erection

An intake of clonidine tablets causes a decrease in heart rate that can result in bradycardia. Unfortunately, bradycardia can be life-threatening. If the heart is unable to keep a rate that pumps enough blood, the brain and other organs in the body will become oxygen-deprived. This can cause other clonidine HCl side effects, including shortness of breath, chest pain, dizziness, fainting, fatigue, and weakness. In rare cases, when the slow heart rate goes undiagnosed for an extended period of time, it may cause complications such as high blood pressure, angina, and cardiac arrest.

Does Clonidine Make One Sleepy?

Norepinephrine (NE) plays a huge role in the occurrence of rapid eye movement (REM) sleep, and Catapres reduces its release. Evidence shows that low doses of clonidine can significantly improve REM sleep and decrease non-REM (NREM) sleep, where the deep sleep stage occurs. At the same time, the study suggests that a morning dose can produce profound sedation as a side effect of clonidine use.

clonidine and weight gain

Does Clonidine Cause Weight Gain?

As an alpha 2-adrenergic agonist, which is clonidine classification, there have been reports of weight associated with Catapres use. This effect was proved correct among patients diagnosed with anorexia. Study results showed a significant increase in the body mass of all patients, though hunger and satiety sensations were not affected. Cessation of drug use resulted in a small but significant weight loss. Still, these results suggest that clonidine indications should not include anorexia nervosa.

Does Clonidine Cause Hair Loss?

Medications cause hair loss by interfering with the normal cycle of growth. The exact mechanism of hair thinning or hair loss during Clonidine use remains unknown. Still, it is reported that Catapres is linked to hair loss and its thinning.

Does Clonidine Make One Tired?

Due to possible sleep disturbances at night and sedation during the daytime, some people feel fatigued. This can negatively affect school or work performance. In most cases, such unusual tiredness goes away in a few days.

clonidine for pregnant women

Catapres During Pregnancy And Breastfeeding

Can One Take Clonidine While Pregnant?

Clonidine and pregnancy can go well together. It does not cause hypotension in both mothers and neonates. No maternal side effects were associated with the drug, too. Catapres is a safe antihypertensive agent in pregnancy.

Is Clonidine Safe While Breastfeeding?

First of all, clonidine passes into breast milk. However, studies on the net effect of Catapres on nursing mothers and breastfed infants are showing mixed results. While most babies did not present with any adverse effect of clonidine despite having nearly two-thirds of the serum levels of their mothers, one positive case has been documented.

Catapres therapy can also affect lactation. In some cases, it has been reported a reduced milk supply in women who took the medication. Because of these possible clonidine side effects in children and mothers, it is best to avoid Catapres while nursing.

How To Manage The Side Effects Of Clonidine?

More common and mild clonidine adverse effects may go away after a few doses or within days because the body needs some time to get used to the drug. Lowering the dose or adding another one to counteract the side effect may be helpful. However, if the side effects are prolonged and are interfering with everyday life, it is best to immediately consult a doctor. Most likely, a new drug will be recommended.

Drug interactions should also be monitored to prevent adverse side effects. A complete list of all drugs and supplements being taken should be presented to the attending physician before prescribing clonidine. Sometimes, clonidine side effects in adults are caused by two or more drugs reacting negatively together. For example, clonidine and Xanax can cause additive CNS and respiratory depression.

Getting Help With Abuse & Addiction

People who have used Catapres for a long period of time, especially in high doses, may become dependent on the drug. Severe symptoms will require professional help. That’s why it is critical to address such symptoms with the professionals from the rehab for drug addicts. Such facilities will provide the needed level of care under individualized treatment for addiction.

Page Sources

  1. Miyazaki S, Uchida S, Mukai J, Nishihara K. Clonidine effects on all-night human sleep: opposite action of low- and medium-dose clonidine on human NREM-REM sleep proportion. Psychiatry and Clinical Neurosciences. 2004; 58(2): 138-44.
  2. Bradycardia. Cedars-Sinai. 2019.
  3. Carskadon MA, Cavallo A, Rosekind MR. Sleepiness and nap sleep following a morning dose of clonidine. Sleep. 1989; 12(4): 338-44.
  4. Casper RC, Schlemmer RF Jr, Javaid JI. A placebo-controlled crossover study of oral clonidine in acute anorexia nervosa. Psychiatry Research. 1987; 20(3): 249-60.
  5. Drugs and Lactation Database (LactMed). Bethesda (MD): National Library of Medicine (US); 2006. Clonidine.

Published on: March 16th, 2020

Updated on: March 16th, 2020

About Author

Isaak Stotts, LP

Isaak Stotts is an in-house medical writer in AddictionResource. Isaak learned addiction psychology at Aspen University and got a Master's Degree in Arts in Psychology and Addiction Counseling. After graduation, he became a substance abuse counselor, providing individual, group, and family counseling for those who strive to achieve and maintain sobriety and recovery goals.


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