Q. I took clonidine for several years to help with both blood pressure and hot flashes. I took the pill only at night. The nightmares didn’t start right away, but after they did, they became progressively more frequent until they were occurring about once every week or so. I became afraid to go to bed anymore, not knowing if I’d wake up in a panic from another nightmare. I also suffered sleep paralysis, which is very scary.
A. Clonidine (Catapres) is a unique blood pressure drug that was first approved by the FDA in 1974. It was first available as a tablet and then later also as a transdermal skin patch (Catapres-TTS).
Although the FDA has approved clonidine only for treating hypertension, physicians prescribe it for a number of “off-label” uses to:

  • Ease symptoms of withdrawal from narcotic pain relievers
  • Ease symptoms of withdrawal from nicotine
  • Relieve hot flashes of menopause
  • Alleviate nerve pain associated with diabetes (diabetic neuropathy)
  • Help control pain caused by cancer
  • Help control symptoms of ADHD

How well clonidine works for these off-label uses remains controversial. Without large-scale, long-term, well-controlled scientific trials it is hard to really know.

Clonidine & Nightmares:

If you check most monographs or standard references for clonidine you will not discover nightmares or sleep paralysis as a side effect. But if you dig a bit deeper into the official prescribing information you will discover that “sleep disorder, and vivid dreams or nightmares” are listed. How common these symptoms are is anyone’s guess. In one informal, web-based study, we found that this side effect may take several months to show up. As a result, it would never have been reported in clinical trials and consequently it isn’t in the standard list of side effects.
Sleep paralysis is another side effect that could easily be missed in clinical trials. That’s because investigators rarely question subjects about this sort of adverse reaction. It can indeed be a terrifying experience. Sleep paralysis sometimes happens upon awakening, when the person just begins to regain consciousness but has no muscle control and feels paralyzed. To get a sense of what this scary situation is like, you may wish to read this account from one of our visitors.

Other Side Effects of Clonidine (Catapres)

  • Dry mouth (40% of patients may experience); dry nose
  • Drowsiness, sedation, fatigue (one third of patients may experience)
  • Dizziness (16% of patients may experience)
  • Constipation (10% of patients may experience); stomach pain, loss of appetite
  • Low blood pressure, especially upon standing (dizziness)
  • Blurred vision, dry eyes
  • Headache
  • Anxiety, nervousness, agitation, restlessness
  • Delirium, delusions, hallucinations, depression
  • Hair loss, rash, hives, itching
  • Fever
  • Sexual problems, loss of libido, erectile dysfunction, urinary difficulties
  • Slow pulse, arrhythmias, irregular heart rate
  • Blood disorders
  • Muscle cramps, leg cramps, joint pain

Does Clonidine Have Anticholinergic Activity?

One of the more disconcerting complications of clonidine is its anticholinergic-like activity. Many health professionals are not aware that this blood pressure drug might alter the way the body reacts to the neurochemical acetylcholine (hence its possible anticholinergic action). But when you see symptoms such as dry mouth, dry eyes, constipation, drowsiness, blurred vision, difficult urination and confusion, they are red flags that the drug could have substantial anticholinergic activity. That means that older people (over the age of 65) could be extremely vulnerable to brain fog, delirium or hallucinations. And such complications could lead to a false diagnosis of Alzheimer’s disease or dementia. To learn more about this under-recognized problem we suggest either our Guide to Drugs and Older People or the chapter on senior citizens in our book Top Screwups Doctors Make and How to Avoid Them. There is not yet adequate research to prove clonidine has strong anticholinergic action, but the common symptoms of this drug are so suggestive that we think researchers should examine this possibility seriously.

Clonidine Withdrawal: A Potentially Deadly Reaction

NEVER stop taking clonidine suddenly! Missing a dose of clonidine can cause a serious or even potentially life-threatening withdrawal reaction. Symptoms can include anxiety, agitation, headache, tremor and worst of all, a sudden spike in blood pressure. The blood pressure elevation can be so great as to trigger a stroke. Although the FDA advises a gradual withdrawal if clonidine must be discontinued, the agency doesn’t provide much detail. Here are the FDA’s recommendations:
“When discontinuing therapy with CATAPRES [clonidine] tablets, the physician should reduce the dose gradually over 2 to 4 days to avoid withdrawal symptomatology.”
The FDA also warns that if a person is taking clonidine and has to undergo surgery:
“Administration of Catapres® (clonidine hydrochloride, USP) tablets should be continued to within 4 hours of surgery and resumed as soon as possible thereafter. Blood pressure should be carefully monitored during surgery and additional measures to control blood pressure should be available if required.”


Clonidine comes with a lot of unpleasant baggage. Although it may be a good choice for some patients, we think it should rarely, if ever, be prescribed to older patients. It is on the “Beers List” of drugs older people should generally avoid. (Other medications on the Beers List can be found in both our Guide to Drugs and Older People and our book Top Screwups Doctors Make and How to Avoid Them.
Have you ever taken clonidine? How well did it work to control your blood pressure? Did your doctor prescribe it for one of the off-label uses listed above? If so, did it work? Did you experience side effects? We would like to learn more about your experience, so please use the space below to enter your comment. Thanks for sharing your story.

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  1. Corine Merritt
    Houston, Texas

    Thank God I found this information regarding Clonidine. I went to the emergency clinic today because my blood pressure was elevating. I told the doctor that I was also having leg cramps. I took a tablet this morning and one before I went to bed. I went to bed at 12:a.m and woke up at 1:30 a.m. with leg cramps. I told that doctor I was having legs camps when I was at his office. I am 78 years old and he should have known better. What is wrong with these doctors………aren’t they required to know the side effects of medications they are prescribing? Thank you for this information.

  2. Rachel

    I take these tables, 0.1 x 3 a day, just stated taking two at night one in the morning, where it used to be the other way round.
    My memory has been terrible, feel like sleeping mid morning – but difficult at work.
    Bad skin rashes (hives) on the skin of my arms, blood pressure, not good, and the blood supply reaching my brain at a slower pace.
    No nightmares yet. and sleep very well.
    I will be making an appointment to come off these tablets, they should be a lot more research done in them.

  3. Christine
    Clarks Summit, Pa

    I have been on Clonidine for years. I don’t even remember when I started them. I take it at bedtime. It’s a 0.3 . I do know that I first started out with dry mouth, dizziness, very tired during the day. This continues even today. I have had a nightmare here and there during the years, but now I have been having them every single nite for about three weeks. They wake me up and I’m shaking and trembling in my bed. I also act out when sleeping such as screaming, talking and even becoming physical. My boyfriend has told me so. I’m at a point where I’m afraid to go to sleep! I will discuss continuing this med. with my doctor next week. Hope to resolve this madness.

  4. Kacie Lee

    I take 0.4 mg of clonidine & I am 15 years old. I have ADHD, so i take clonidone for sleep. Anyways, I experience light headedness, rashes, skin agitation, irregular heartbeat, Low sex drive, etc. When I don’t take my medicine for a day or two, I tend to shake really bad.. I feel like everything around me is fake… My anxiety is awful.

  5. Bobbi

    I have headaches and a badd dry cough that make me throw up. I have been winging myself off this mess so that I won’t have to take it anymore, I have missed 3 days and then took one tablet on the 4th day and will repleat this again. This medicine is just not for me.

  6. I. Y. Domingo, Jr.

    I started taking Clonidine since 2010 and experienced dry mouth, awake at night and some joint and painful leg muscle cramps, headaches, blurred vision, back pains, are my symptoms and started having the same nightmares which was mentioned here in the forum.

  7. Jim
    Brevard, NC

    I’ve taken Clonidine for a number of years. Dry mouth, awake at night and possible joint cramps are my symptoms. I’m never confused and do not have strange dreams.

  8. Mildred H

    Mildred H. I’ve been on 0.1 MG TAB of Clonidine for several months. 2 at nite. 1 on rising. My Dr tried newer drugs. Very adverse reaction.
    I have stress related blood pressure, which is hard to treat. Since 1981 I have been on & off BP med probably 8 or more times.
    When stresses are dealt with and relieved, BP med overwhelms system to the point of my falling on bed when making it. Precarious spot to be in.
    My BP was at 220/110 w/ pulse at 111 when my son and I left for the funeral home. I had taken an extra BP med attempting to lower it. Mom, 2 days short of 94 lay in her coffin. Others stresses were also in play. This was on May 24th.
    Unexpectedly I spoke out to the congregation about my mom in a vet negative manner. I know this because of all the repercussions that have come against me since. I, myself do not remember any of the words I spoke, only the topics. They were Mental Health & Commitment to vows of marrive.
    Apparently I spoke my mind on both subjects.
    This speaking out has carried horrible emotional upheaval in me.
    I’m very interested in knowing that answer to these questions.
    Thanks. Mildred H. June 9, 2016.

    • Terry Graedon

      We don’t know if the clonidine caused your atypical behavior. Overdosing (the extra dose) can cause blood pressure to go up at first, and then drop precipitously. Hallucinations may occur. Here are the psychological side effects of clonidine, according to DailyMed: “Agitation, anxiety, delirium, delusional perception, hallucinations (including visual and auditory), insomnia, mental depression, nervousness, other behavioral changes, paresthesia, restlessness, sleep disorder, and vivid dreams or nightmares.”

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