Overview

Cetirizine is an antihistamine used to treat allergies such as hay fever. It alleviates symptoms of runny nose, itchy, red, watery eyes, and sneezing.

Zyrtec has also been found to be helpful against hives and itching of the skin.

Cetirizine works by blocking histamines released in the body in response to allergens. When it was introduced, it was not expected to cause sedation. At effective doses, however, cetirizine may make many people feel drowsy. A closely related drug, levocetirizine (Xyzal) is available only by prescription in the US.

Side Effects and Interactions

The most common side effects of Zyrtec include drowsiness, dry mouth, fatigue, and dizziness. Constipation, nausea, headache, sore throat and cough are not unusual. Rare side effects may include tremor, increased appetite, weight gain, ringing in ears, muscle pain, skin rash, hair loss, and liver enzyme elevations. Report any symptoms to your physician promptly, but especially such potentially serious side effects as
• Confusion, restlessness, hyperactivity
• Fast, pounding, or uneven heartbeat
• Sleep problems, weakness, uncontrollable shaking
• Vision problems
• Urinating less than usual or not at all
Be aware that it may be difficult to discontinue cetirizine if it has been taken continuously for some time. Many people experience intolerable itching for several weeks if they stop the drug abruptly.

Drug interactions are apparently uncommon, though alcohol and nervous system depressants could add to the sedative action of cetirizine.

Special Precautions

Older people and those with kidney or liver problems may not eliminate cetirizine efficiently and will likely need a lower dose.

Because this antihistamine may cause drowsiness it could make driving dangerous. This is also true for any task that requires mental alertness.

Do not drink alcohol or take other sedating drugs, as it could add to this effect.

Taking the Medicine

Food has very little impact on cetirizine absorption and consequently this medicine can be taken once a day at a time that is convenient.

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  1. Jason
    USA
    Reply

    I am taking cetirizine for allergies. It really helped with asthma, but I stopped because I ran out. Then I took loratadine cause store was out of cetirizine, but I got a cough and glue taste in mouth. Not sure if it was because of going off the cetrazine or getting on loratadine, but scalp itched really bad. Now I am back on cetrazine. It’s cheaper than an asthma inhaler.

  2. Lisa C
    Reply

    Hi guys, I’m overwhelmed I found this site. I got delayed pressure urticaria and angioedema 10 year ago. Intense itching in hands feet, massive welts hives. I got put on this drug in hospital then seen an allergist. I have taken 2 tablets 20mg every night for 10 year. Like yourselves I get itchy palms every 24 hours when I’m due tablets so thought i still had urticaria ect. My health has declined over the years. Have had muscle and joint pains for 10 year, diagnosed fibrmyalgia. Diagnosed with chronic fatigue last 4 year.
    Started getting really bad flares the last 5 year, feelings of trapped nerves, dragging legs, pain behind eyes, waking up in middle of night with severe back pain, which I have found out it muscles going into spasm in lower back. Weakness, very poor concentration, exhaustion, numbness, pins and needles hands and feet, the list goes on. Every test I get comes back negative.
    Recently seen a neurologist because gp thought it could be ms. Results…negative, I swear they all thinking I’m making it up what is happening to me. So you guys I’ve done more research and was shocked to find out that this drug is a central nervous system stimulant (brain, spinal cord) and clearly states this on NHS(UK) website as the word CNS for short. So here’s a website http://www.drugs.com/pro/cetirizine.HTML its research into longterm effects of this drug, if scroll to the bottom of page you will be shocked at the damage it can do, to nerves in your body ect. I’m ringing docs Monday to try come off these, I’ve never missed a dose in 10 yr so taking advise from comments here and try ween myself of them. Sorry I’ve waffled but I’m so angry at what this drug has done, good luck to you all.

  3. Beth
    Reply

    I took generic Zyrtec – Cetirizine for about 7 weeks. I loved it at first. I didn’t have a headache everyday, no post nasal drip. Ahhh, it was great.
    After being an irritable, anxious, snappy hag for a couple weeks I started to do research on cetirizine. Needless to say I stopped that day.
    I have been off for 1 week now. I have periods of severe, uncontrollable itching. It feels like insects are stinging and biting my body. I try to ignore the itching and my heart starts to race. Then I get shaky. Then the anxiety kicks in. I can’t focus. Couldn’t care less about sex. I’m hating everything right now.
    Xanax or Lorazepam are the only things to help my anxiety. I have taken Benadryl when the itching attacks my entire body.
    As I type this my thumb, hand, forearm, knee, ear, and hairline are itching. Aaaarrrggghhhh.
    I am telling everyone I can about this drug. Stay away.

  4. Linda
    Reply

    I have taken Zyrtec for many many years. My Dr actually prescribed for me to take 2 a day, morning and evening. Several yrs back I started buying the Costco brand that is equivalent to Zyrtec. All the time I was taking the name brand and Costco brand I noticed no ill effects BUT I had not tried to stop taking it.
    Approx. 2 months back or so I tried Walmart’s Equate brand of Cetirizine Hydrochloride (equivalent to Zyrtec). Within a week I was so run down and tired it was hard to function. The joints in my body were very painful and warm as well. I have systemic Lupus so I thought I had a flare-up of my Lupus. The flare-up seemed to be lasting too long (medication taken to lessen flare-up) but again I gave the allergy med no thought.
    About 1 week ago I ran out of my Equate brand Cetirizine. My allergies were not horrible so I decided to see how I do without it. Well, I feel as if I have been through (and still slightly have) full blown drug withdrawal. No itching (which is odd after reading the above comments) but the second night I had severe vomiting that lasted throughout the evening into the early morning. I had what felt like anxiety, a severe headache and my body was quivering inside and out. The vomiting and headache were gone in less than 24 hours but I was left with this intense anxious feeling and quivering insides. My heart will take off at a very rapid pace and feel ‘fluttery’. That is accompanied by shortness of breath and an overall anxious and scared feeling. There are multiple times throughout the day where this comes and goes. I notice it more so at night when I’m laying down. Oh, and the joint pain? It’s almost completely gone now. Never would I have thought that a medication sold over-the-counter could be so harmful to the human body.
    I am well on my way of being rid of this in my body and will not take it again. I don’t know what allergy medication I will use to replace it when needed but rest assured I will research it thoroughly BEFORE use. We are our own best advocates and over the last 20 yrs or so it seems drugs are being released for consumer consumption with a whole list of seriously negative side effects. I feel as if we are now the lab test subjects for the pharmaceutical industry.

    • Olivia D
      Florida
      Reply

      Hi HH.

      I have been off Zyrtec for about 6 days now. I was on it for about 6 years, 1 pill every night before bed. I have noticed the itching, no hives but I am having extreme anxiety. At night its the worst and the mornings are pretty bad. Almost like a mild panic attack feeling.
      I was wondering if your symptoms have gone away and how long did they last for? :(
      I’m trying not to resort to xanaz or any anxiety medicine. I’m just curious how long you felt the way you did when stopping?

      Thank You so much.

    • Olivia D
      Florida
      Reply

      Sorry.. Hi Linda!!
      I looked at the wrong post for your name.

  5. HH
    Reply

    I have had extremely aggravated Restless Legs Syndrome every night this week that I have taken a generic Zyrtec. Usually, this only happens when allergy meds have diphenhydramine listed.

  6. eli
    Reply

    I used ‘Zyrtec’ for about 5 weeks and developed this horrible rash. I have stopped taking the ‘Zyrtec’ and the rash is finally starting to subside. I have tried so many things to help relieve the itching. The best thing so far has been zinc oxide cream. I will never take this medicine again and will warn others.

  7. mol
    Reply

    I have been taking zertec for about a week now, and have been experiencing this horrible nonstop coughing. So I didn’t take it and the coughing hasn’t stopped and now I am pretty much choking on my coughs. I am not worried about the hives that you guts have been saying you got from just stopping the zyrtec, because I would get them on a daily basis and sometimes multiple times a day. Have any of you experienced this while taking zyrtec? If so I’d really like some help because I am also very athletic and all this coughing is making sports difficult and if often keeps me from even sleeping at all.

  8. SB
    Reply

    In case it’s useful to others, I purchased Kroger’s all day allergy cetirizine hydrochloride tablets, 10 mg antihistamine, which they promote on the packaging as comparable to Zyrtec.
    Within a very few minutes I started to feel like I was in a coma. I was dizzy, mentally and physically extremely sluggish, and utterly exhausted. I was too foggy to even watch t.v. or read. For the past two days, most of the day I have laid on my bed, feeling dizzy and sleeping (first day) and sleeping second day. I forced myself up for an hour or two each day by force of will, but moved through the house with difficulty feeling like a zombie. This medication was extremely toxic to me.
    If I had studied all year to take the bar exam, I would have had to miss it. Likewise if I were getting married, making a career defining presentation etc. This medication made me THAT sick.
    Of note is that on the dosing directions on the bottle, it says: “a 5 mg may be appropriate for less severe symptoms.” However the outside package did not include this disclaimer and the Kroger did not stock a 5 mg product. People purchase the product based on the outside packaging dosage recommendation and this reads “our pharmacists recommend.”
    There is no antidote for this product according to medical sources on the internet. LOTS of other people have apparently had the same reaction I had. Some posts on the internet suggest that though this is a “24 hour” product, it is not a time release product and CAN be safely cut in half. High recommend any first time user buy the 5 mg product (if they can find it) or cut the product in half or less (after verifying with a pharmacist that this is safe) to insure that they can safely take it. You can always take more, but can’t rid your system of it after taking it, other than just waiting for time to pass.
    I’m sure I would have had an adverse reaction to the 5 mg product as well, but it probably would have been half as bad. I took the medicine almost 48 hours ago and am only now BEGINNING to return to normal after being passed out another 12 hours of drugged sleep last night (36 hours after taking the product). And still VERY hard to get up.
    Thanks to the Peoples Pharmacy for giving the consumer a voice and for so much more.

  9. tom
    Reply

    5 weeks ago, I came to see doctor at my local walk-in clinic. I had some itching areas on my back shoulders and both sides of my ribs. He said it was an allergy and prescribed me PMS-CETIRIZINE 20MG. I took 1 pill each day as he instructed, for 2 days. I stopped taking it, because I felt lousy and shutdown. My itch started to flare up and spreading to other areas of my body that had no itch previously: chat, forearms, elbows, back of neck, thighs, calves, head, forehead, feet, toes, hand knuckles, around nails, behind the ears, inside of the earlobes, cheeks.
    I am scratching until I bleed. The itch on the head is like having thousands of Ants biting, and it keeps me up all night. I was given topical cream like Topicort, Hydrocortisone, Ectosone, Clobetasol, but they haven’t been helpful. The itchy areas have little bumps, some of them red, some not. Most areas have bruises and bleeding scratches. I am not sure if two pills of cetirizine would do all that as “withdrawal” side effects, but I can’t think otherwise! Both my GP doctor and dermatologist insisted that I have an allergy since the last week of Feb until now. This website is a real eye opener. I will bring it up to my GP doctor at my next appointment.

  10. Dianne
    Reply

    I have had Cold Urticaria for 25 years. I first notice the itching on a hot summers day when suddenly the clouds came over. After this, it happened when I took the dog out a night, and would arrive home with itchy red rashes on my legs. Once indoors, it would quickly disappear. As I’ve got older, I now have to take an antihistamine everyday to avoid itching from head to foot constantly.

  11. H
    Reply

    It was suggested to me by my doctor to try an histamine to help flushes and headaches as I work in a stuffy office. I went to the boots pharmacist and was shown the various tablets. I did check the side effects and started the taking the tablets. I knew after the third day taking the tablet something was not right and stopped immediately and consulted my doctor. I did experience some side effects like dry mouth and hair and scalp felt alive and crawling and experienced some itching when using perfumed shampoos. Will I have suffer any long lasting effects after only 3 tablets and how long does it take for the drug to completely leave your body?

  12. marion r.
    Reply

    After reading this I have been taking cetrizine 4mths. N allergies thought they weren’t working developed itch arm. Not knowing about this I had stopped taking them. Which I now know was withdrawal I am back on them for 3mth no itch but joint pain. I am now going to stop this drug. And will wean myself off hope its not as hard as u people say day 1 half tab for MTV take it from there.

  13. T. Slezak
    Reply

    Did your joint pain go away?
    My daughter took Zyrtec over a year ago and still has chronic joint pain and no longer can attend school & is in a day hospital program at a local children’s hospital.
    I spoke with someone at Zyrtec who of course said they have no knowledge of Zyrtec causing joint pain, but this is a crazy coincidence.
    T. Slezak

  14. Kimberly H.
    Reply

    Hi Robyn!
    The way you described your Zyrtec withdrawal itching (starting in the hands) sounds identical to the way my body responded to Zyrtec withdrawal, so I wanted to respond in case this helps!
    I’ve posted a few times on this page describing the “weaning” process that I tried (after reading about it on a page like this one) that allowed me to quit Zyrtec. If you press Ctrl+F and search for “Kimberly,” you can read all of my posts above, but I’ll also just paste the content of a previous post below:

    I tried for years to get off Zyrtec but had terrible itching any time I missed a pill!
    My first attempt to quit Zyrtec was to go cold turkey. I made it ten days (itching and uncomfortable) but then broke out in hives (even though I was NOT scratching). I decided that was not a reasonable option for me since my body was reacting so strongly and since I was in school at the time and had things to be doing.
    The second (successful!) attempt I made was to wean myself off of Zyrtec by cutting my pills in half. I did this in a few steps:
    1. I cut my pills in half for about six months or so.
    2. I then tried cutting my pills into quarters, but the itching returned.
    3. I resumed taking a half pill every night for a while.
    4. I then tried taking a half pill every /other/ night. This resulted in NO itching for me.
    5. Then, after some time (maybe six months or a year) of taking a half pill every other night, I decided I was prepared to go cold turkey.
    I expected to have the 15-day detox period described on some of the blogs, but, to my pleasant surprise, I had only very mild itching (and kind of a warmness in my face) for a couple of days, and then I was fine. (That was four years ago).
    I know how frustrating this incredible Zyrtec-itching is, so I’m eager to share the weaning method that worked for me. Lots of luck and health!

  15. Robyn C.
    Reply

    I am having the same symptoms, I cant get past 36 hours without taking it again. The itching and burning starts with my hands and by the time I go to bed my feet, legs, trunk all itching… The symptoms stop within about 1 1/2 hours of taking again. I really don’t want to keep taking but the itching drives me insane. Please Help.

  16. Jennie
    Reply

    Day 60 off of Zyrtec-d. I am still itching in any area that grows hair (scalp, armpits, etc)… gained 15 pounds in 60 days and I’m a vegetarian fitness instructor. I am seriously considering going back on the drug.
    I can’t live like this and feel no one believes me. Oh, and my nasal allergies are horrible. I snore now and I’m anxious. This stinks.

  17. Shelley
    Reply

    My 5yo son was prescribed cetirizine syrup as he had allergic rhinitis for many weeks. I was very concerned when the dr said to take it for 12 weeks and see how it goes – there was also a steroid nasal spray. I was concerns a bout my sons blocked nose and post nasal drip which was interfering with his sleeping. After 3 weeks on the medication the symptoms were still there but a little better.
    After reading some comments online I didn’t like the potential side effects of the drug so I tried to wean my son off – he immediately got clogged up nasally and began to itch. I did some research and tried a different approach. I began him on a course of probiotics – first the acidophilus type and then as I researched more I changed to the rhamnosus type which he been shown to repopulate the nasal passages with good bacteria and help fight against staph etc – I continued the cetirizine 5mg per day and one spray – the symptoms began to ease!
    After 2 weeks there was no nasal discharge but I felt his nsal passages were getting too dried out by the antihistamine and his sinus were gettin sore e.g forehead – so I decided to stop the antihistamine cold turkey and keep one or two sprays a needed – my poor son got the itches really bad but I knew from this site we had to keep going – none of the sinus or nasal symptoms reappeared but he had bad itches and skin crawling for 2 weeks!!! But I just distracted him and had other children over to play to wear him out so he at least had good sleeps – btw ALL allergy symptoms were gone!
    Now we just had to deal with the cetirizine withdrawal arggggh. But happy to say he is now OFF cetirizine and the steroid spray was only used for 4 days after stopping cetirizine. The probiotics seems to work and he takes one rhamnosus cap every day. I believe the courses of antibiotics he had taken the previous year had wiped out his good bacteria and his nasal passages were shot – however the fear mongering dr said his allergic rhinitis could lead to asthma and he would have to be on cetirizine for the rest of his life!!!!
    So grateful for this blog and also science for showing me that getting to the cause is much much better than treating symptoms. Note – no environmental changes so must have been the probiotics as this was the only change that allowed me to cease and desist with the antihistamine drugs. My son is over the withdrawal and it wasn’t too bad – worth it to get him well and OFF this horrendous drug. Sleeping like a baby – no nasal blockage – no post nasal drip – no asthma – and NO cetirizine.

  18. MDM
    Reply

    I have taken a cetirizine based product for hayfever after the British spring & summer hit all at once bringing with it all the different types of pollen in one handy hit.
    In previous years I have taken claritin products which have always been sufficient, but this year didn’t even touch the more severe hayfever symptoms I have experienced.
    All in all have been taking cetirizine for around 2-3 months.
    I stopped taking hayfever medication about 2 weeks ago now. I don’t seem to have experienced the itching other people seem to commonly be describing in this thread (or at least if I have been itching it has been relatively mild). Instead, two days into to cold turkey I awoke from sleep in the middle of the night to the most overwhelming and quite frankly terrifying feeling of anxiety.
    Following on from this, leading up to day 7 I have experienced an increased heart rate and palpitations as well as an upset stomach. Thankfully this seems to have subsided now and I generally feel much calmer and am sleeping now.
    I didn’t even make any connection between stopping taking hayefever medication and the symptoms I describe above until I was talking to some workmates about it and one suggested looking up withdrawal. I’m glad I did as I was starting to think I was going mad or at the very least something was very wrong with me!!!!
    Day 13 and for the past couple of days I have felt dizzy when standing up and moving. I can sometimes suffer from an inner ear condition called labrynthitis which makes you feel dizzy and spaced but this would normally continue when I lie down so its hard to tell if this is to do with my ears or yet another fun come down symptom. Has anyone else experienced dizziness? When did they start and how long did it last for?

  19. Michelle
    Reply

    My daughter’s pediatrician prescribed OTC childrens Zyrtec for her for mild seasonal allergies when she was two years old. Up until this point she was a very happy, pleasant child who was a joy to be around. After we started this medication her entire demeanor changed. We thought she was having the terrible two’s on steroids. She was angry all the time, she had constant meltdowns over the tiniest things, she was violent with other children at the babysitters and almost the worst part was that sometimes she would look at you and you could tell that at that moment, she hated you.
    I happened to mention to my sister at one point after this started that Linnie was on zyrtec. She told me to take her off of it right away. Turns out that my sister has the same reaction to this drug. Linnie returned to her normal loving and pleasant self within a few days of stopping the medication. I can’t recall if she suffered any withdrawal symptoms as I was not aware of the possibility at the time. I’ve taken zyrtec myself off and on for the past few years, but lucky for me I’m bad at remember to take my meds.
    I may have had mild withdrawal symptoms in the past, but not bad enough for me to really take notice of. I started to take it again this spring, but have noticed mood changes the few times that I have taken it. I’ll be switching to claritin or allegra.

  20. MA
    Reply

    Have been on Z 10 mg. 2 pills 2x a day since Feb. for itching snd hives due to reaction from contrast media. Also was started on Doxepin 20 mg. nightly for persistent itching and dermatographia. Experiencing bad pain in knees and thighs. Put it up to my job… on feet 10 hours daily. Saw allergist today who told me side effects of Zyrtec too numerous to increase dose… had been getting breakthrough hives. Increased the Doxepin tonight and will start weaning off Zyrtec. Hope I can get off or at least cut down.
    The knee pain and thigh aches are 8-10 on a scale 1-10. I can’t take NSAIDS as they increase the itching…. or pain meds due to my work as an RN. Pain so bad it wakes me up.

  21. Lesley
    Reply

    I’ve never had allergies until I moved to Nevada. I decided to try Zyrtec after reading some positive reviews. I wake up feeling so groggy and wanting to sleep for more hours and hours. My mouth does get really dry and cottony… I wonder if I should just take as needed or half dose. I’m going on vacation on Thursday to Texas.. could be new allergy there… but don’t want to be a groggy zombie either.

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