Drug Ratings for ZYRTECAverage Rating: 2.1 (1499 Ratings)
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Results are sorted by length of time drug was taken from longest to shortest Key to Ratings: 1=LOW (I would not recommend taking this medicine.) Page: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 |
| RATING | REASON | SIDE EFFECTS FOR ZYRTEC | COMMENTS | SEX | AGE | DURATION/ DOSAGE | DATE ADDED |
  | F M | | | | |||
| 3 | allergies | short-term memory loss, fatigue, bad mood, mood swings, lack of concentration, decreased balance and motor skills, insomnia, anxiety, increased appetite with sugar cravings, constipation, bloody nose when dry or running. | It got rid of my severe mold(?) allergy symptoms quickly, but I felt like a zombie. The worse being lack of mental clarity and fatigue. | F | 23 | 5 days | 3/31/2008 | 3 | Allergies | Confusion, forgetting alot, talking in my sleep and sleep walking. | I've only been taking zyrtec otc for less than a week. I'm convinced my sleeping problems and forgetting things that I shouldn't be forgetting are because of the zyrtec. The first day I took it, it was in the middle of the day because my allergies were so horrible I just wanted them to be lessened a bit. Started taking them at night and now I talk in my sleep and sleep walk which I have never done. I'm also forgetting things that I shouldn't be forgetting. I can't say whether or not its helped my allergies because it was a full blown allergy attack when I first took it. It lessened my symptoms dramatically but they haven't dissapeared completely yet. I'm going to continue taking it for a while and hope for the best. | F | 25 | 5 days | 1/15/2009 | 2 | seasonal allergies | the main side effects that were a problem were a major change in emotional outlook and irritability. After just a couple of days on Zyrtec my patience grows very thin and I am frustrated and angry with everything. This time, after several days, I also started having pretty dark thoughts, almost suicidal, which is not like me at all. The worst may be that I am unaware of what is causing it and unable to really see the changes in myself accurately until after I stop taking it. The rest of the family sure notices immediately. When I stop after it leaves my system it is like a massive cloud just dissipates. I only use occasionally to manage bad allergies, but I have now decided I cannot take it again. | It works well for my allergies but I cannot handle the side effects. I usually only take a few times a year and for a week at a time at most, but it is causing big issues in the family and this last time I seriously was in a very depressive state, it was scary. | M | 43 | 5 days | 12/2/2008 | 2 | Allergies | This medication made me so drowsy that I couldn't function during the day. I would stumble around almost in a trance. | It helped my allergies to a degree, but the extreme drowsiness it causes isn't worth it. | F | 20 | 5 days | 5/24/2005 | 2 | ongoing allergies & sinus problems | This made me so drowsy I could not function. Could not drive, was lethargic, felt drugged. | Seemed to help my allergy symptoms tremendously but the extreme drowsiness and drugged feeling were more debilitating than the allergies. In other words, this made me feel worse than did the problem for which I was taking it. | F | 31 | 5 days | 10/17/2004 | 2 | allergy cough that is always there | With-in an hour I felt morbidly depressed and hopeless. I thought it was my imagination. But I had the same outcome for the entire 5 dose package about 10-40 minutes after taking it. After I stopped, this completely stopped! Then my left eye started acting weird-like spots that come and go. | It did help the cough. One of the only things that ever has.. But now I am spooked about taking it. I wonder if this medication has any impact on eyes (retina/ response to bright light) or if that has been considered? My eye is still not right. I see a DR Friday. Kind of scary-these drugs with their harmless happy-go-lucky candy store advertising. | F | 48 | 5 days | 6/10/2009 | 2 | seasonal allergies | My 5-year-old developed an extremely volatile mood tending toward tearfulness, depression, erratic sleep patterns. This occurred on the day I started giving him Children's Zyrtec and ended the day after he ceased to take it. | M | 5 | 5 days | 3/3/2009 | 2 | seasonal allergies, sinusitis | interrupted sleep, strange dreams, waking up exhausted, extreme fatigue all day with intermittent bouts of extreme hyperactivity and restlessness, inability to concentrate, irritability, extreme frustration for no reason, anger, mood swings, anxiety, depression, both insomnia and hypersomnia. | Although Zyrtec definitely helped my constantly runny/stuffy nose and other allergy problems, I would not recommend taking it. The side effects caused more problems than my allergies. I would definitely recommend taking something else, Zyrtec is not worth it. | F | 21 | 5 days | 6/15/2008 | 1 | allergies | my 4 year old has been taking Zyrtec for 5 days and over the past couple days he's been tantruming much more than anytime in the past many months. I did a web search on zyrtec and behavioral problems in kids because he's increasingly not been able to deal with situations that he usually would be able to handle -- finding this website and the many, many comments about similar reactions to zyrtec quickly convinced me to stop giving zyrtec to my son. | M | 4 | 5 days | 5/3/2008 | 1 | seasonal allergys | 8 yr. old daughter groggy in mornings then 4 days into she started having severe asma attacts stopped taking all went away | the stuff is dangerous | M | 5 days | 7/16/2009 | 1 | hayfever | I took only 5 doses in March 2009, it cleared up my runny nose and I could breath again. BUT I lost my complete sense of smell! I can't smell at all and I use to have a very good sense of smell. Now days I might get a small whiff of something but it's very rare. | I had never taken this medicine before, this was my first and last time. I want my sense of smell back so bad. | F | 53 | 5 days | 8/23/2009 | 1 | Alergies | Severe back and tummy ackes thought it was apendix | This drug should not be out on the shelves I am 23 yes old and never felt such pain in all my life .it made me feel week nautous I actialy through up many times I had severe stomach pain in my lower intestines and severe pain in my kidneys it felt like someone was sucker punching me a/ knifes | F | 23 | 5 days | 5/5/2009 | 1 | seasonal allergies | I was a zombie 24/7. Couldn't function and it was affecting my mood. My two-year old who is normally very sweet-natured turned into an aggressive manic. | Horrible side effects. It barely took the edge off of my symptoms, but it did clear up my son, although at a price that I'm not willing to pay. | F | 33 | 5 days | 4/28/2009 | 1 | seasonal migraine headache control | 5 pound weight gain after just 5 days of medication! cognitive impairment, vivid dreams | F | 54 | 5 days | 4/20/2009 | 1 | coughing, allergies | My 3 yr. old son was taking this medicine, prescribed by our Dr., for 5 days. Since he started taking this he has had major breakdowns over the littlest things. I associated this with his age, but wondered why it just happened over night. I was telling a friend of mine about how he had became very angry, was back talking, hateful, and very emotional. He would have temper tantrums like I have never seen him have before, even in public...which never happened. She was telling me about how her Dr. wanted her son to take this too, and so she researched it. She found that many moms were complaining of these same symptoms so she chose not to use it. I decided not to give it to him this morning and I can not believe the difference it has made. We were blessed that he hadn't been on it long so hopefully he will just continue to quickly improve. | F | 31 | 5 days | 11/2/2009 | 1 | Allergy induced asthma | moodiness, depression, irritable | This drug is TERRIBLE! I can't believe it's sold over the counter. After just 5 days, I was so depressed, I could barely concentrate at home and work. Find another way to treat your allergies! | F | 45 | 5 days | 9/21/2009 | 1 | eczema, allergies | my daughter is four years old and the zyrtec side effects were just terrible. She was acting out of control and very difficult to say the least. She was very aggressive at preschool and that was a direct result of this drug as she has had no problems in the past. This was recommended to us to use by a dermatologist, but I would not recommend it AT ALL for children's use!!!!!!!!!!! | F | 40 | 5 days | 9/23/2009 | 1 | allergies, sinus headaches | Extreme fatigue. I took it at night in hopes that I would feel better in the morning and I was wiped out all morning. I even tried splitting the 10mg tablet in 1/2 and seeing if that would help but no luck. I have switched to Flonase and OTC NasalCrom and I have been very happy withe the results. I would avoid Claritin, it gave me scary irregular heartbeats. | F | 32 | 5 days | 4/4/2005 | 1 | seasonal allergies | tiredness, irratible, itching | I have been on this medicine for about 5 days. I have been wiped out but assumed it was a spring cold. I basically slept all weekend and was so exhausted that I was incapable of caring for my three young children. I feel like I am in a fog. I have also have zero patience with my husband or children for the past several days. Then, the itching on my face started! It was only when I read this site that I realized my extreme overtiredness and irratibility may be caused by this medication as well. The face itching is unbearable and I am going to stop immediately. I just hope I can get this out of my system quickly! | F | 34 | 5 days | 5/2/2005 | 1 | Inner Ear fluid | Rage | Had several outbursts within 1 week of taking drug, had an almost infinetly short fuse. I don't think any benefit would be worth the cost. | M | 43 | 5 days | 5/1/2006 | 1 | pollen allergy | high level of irritability!!!!!!!!!!!!!!!!!!!! | If I could have given this drug a negative rating I would. About 5 days ago, I started taking OTc Zyrtec-D for my spring allergies. Helped with sneezing during the day, , did nothign for itchy eyes, increased itchiness in throat, did nothing for congestion, and yet I was still left with a drippy nose. Incredibly uncomfortable since I now have blisters forming on my nose from where I've rubbed a tissue all day. Was really irritable this week which has culminated in several arguments with my wife. Not sure if the irritability is a side effect of the medicine or just a result of paying over $1 per pill and still being left with most of my symptoms. FYI, I am writing a complaint to the makers of this drug. Probably won't do any good but it will at least make me feel better. | M | 27 | 5 days | 3/28/2008 | 1 | Allergies | Very very bad headache migrain like, loss of appetite, trouble focusing, trouble paying attention, right side of neck swelled up and bothered my ears, fever, & allergy symptoms worse. I could have a head cold but I swear I was fine untill I took 3 of these pills I just got progressively worse. Dont take this over priced medicine. Advil Cold and Sinus is #1 for me. | F | 25 | 5 days | 3/17/2008 | 1 | allergies | I would get violent and take it out on my wife, especially when she makes meatloaf. She would get a swift kick to the stomach and I would proceed beating her across the head and throat. I would then turn green and smash through the door. | It doesn't taste good. | M | 22 | 5 days | 3/4/2008 | 1 | Chronic post-nasal drip/allergies | increased blood pressure, heart palpitations, anxiety | 5 days ago my doctor prescribed Zyrtec to deal with chronic post-nasal drip due to allergies. After the first day of taking (at night), I woke up feeling anxious and my heart was fluttering/palpitating. Since these were not listed side effects on the insert, I thought that perhaps I was just having an off day. Five days later and feeling the same, I was having a check up with another doctor, who informed me my blood pressure was 130/96 when it had been 120/70 just 5 days before--which is also strange because I am fit and otherwise healthy. I called my primary care doctor, who said to discontinue the medicine because it can have cause increases in blood pressure and tachycardia. | F | 26 | 5 days | 2/5/2008 | 1 | seasonal allergies | stomach pain w/upsetting bm's, restlessness, unusual tantrums, nightmare's, crying, mood & personality changes | After not having much success with Benedryl or Clariton for my 5 year old's allergies, my pediatrician reccomended Zyrtec. Initially the stomach aches started. Each night my son would wake up and come into my bed complaining of nightmares, something he had not done in years. Witihn 3 days I noticed his inability to sit still, which became significantly worse each day! By day 5 he was out of control, a totally different child!! And, as one other parent wrote, non-compliant, desrcribes it well, way beyond what is normal for a 5 year old boy, and very unlike any behavior he's exhibited in the past. By the evening, he had a full blown tantrum of which the likes he has not exhibited since a toddler. I decided to check this Zyrtec out and boy am I glad. He will never take another pill. I am outraged that my pediatrician never mentioned this, nor were these side effects listed on the information sheet provided with the prescription. | M | 5 | 5 days | 7/11/2007 | 1 | Post nasal drip and allergies | Anxiety, depression, suicidal thoughts, nausea, diarrhea, gas, heart palpations, flushed cheeks, confusion and sensitivity to light. | This stuff is SCARY! I am a 41 year old man and this stuff had me breaking down in tears within 48 hours. I would just start crying over the smallest things. I'm currently unemployed and, although that's pretty stressful, I have never thought about suicide until I started taking Zyrtec. I was nauseas, had diarrhea, and if it wasn't for this website, I probably wouldn't have figured this out! I stopped taking it and I am slowly returning to normal. However, I switched to over-the-counter Claritin and I still have the mild nausea and flushed face. | M | 41 | 5 days | 6/7/2007 | 1 | allergies | Anger, tiredness, lack of appetite, night terrors | I have just tipped my bottle down the sink!! My 3 year old was on this off and on during the spring for allergies. While it helped with the allergies it turned my wee man into a tantrum throwing brat. The worst part was he ended up having night terrors and it would take hours to calm him down, never again!! | F | 41 | 5 days 5ml 1X D | 11/11/2010 | 1 | allergies | sleep problems, fast heartbeat and most recently night terrors after stopping dosage for 2 days | My recent allergy episode was so bad that I took Zyrtec and continued to take it for about 5 days. When the allergies got better, I stopped taking the drug. I woke up drowsy, sleepy and very irritable this morning. An hour later, after sending my son off to school, went for a nap and woke up 6 hours later from an upsetting dream. I was sluggish throughout the afternoon and early evening. Finally went to bed and shortly afterward began having night terrors for the first time in my life! I couldn't breath, felt paralized and had to lay there until I calmed down. Will not recommend this to anyone especially children. But for parents whose children are on this medication, I would suggest contacting a doctor as stopping the drug IMMEDIATELY HAS ITS OWN SIDE EFFECTS. Good luck. | F | 41 | 5 days 1X D | 11/17/2010 | 1 | allergies | I was in tears today with my 4 yr old daughter; she was soo negative and moody, throwing tantrums and being defiant. She usually is the sweetest child, caring and helpful. She was soo rude, saying no and actually pushed her little sister today in frustration/anger. Thank u sooo much for this site, i am no longer giving her this medicine. thank god i didnt keep her on it longer!!!! | F | 4 | 5 days 1.5 ml 1X D | 1/2/2011 | 1 | Seasonal allergies | I began taking Zyrtec because the Claritin was not working for me. I noticed the allergy symptoms clearing very quickly. HOWEVER, by the 4th day a dark sad mood came over me - for no apparent reason. (I am a 44 year old woman that understands her body well - when I am hormonal, etc. This was not hormones.) By the 5th day, I was feeling suicidal and extremely concerned by the depression closing in on me. I was also very very tired, even though I had slept 8 hours the night before. | Then, I remembered that we had taken my 9 year old son off of Zyrtec because we thought it was affecting his moods. Apparently, we were right... his out look on life and his general mood changed drastically a couple of days after taking him off Zyrtec. For some reason, I thought I would be immune to the side effects. But, I was not. I would recommend NOT taking Zyrtec. | F | 44 | 5 days 10 mg 1X D | 2/10/2011 | 1 | For very bad hayfever | I suffered from feeling depressed, extreme anger and at one point lost control and became violent, which frightened my family and me. My wife urged me to come of the drug because she put two and two together as this was not my personality trait. This drug which is also in Pyreteze and many of the one a day allergy tablets. I went to the pharmacist in Sainsbury who looked up side effects in her book and she confirmed that depression was one of them. | I would rather suffer from hayfever than ever recommend this dreadful product! | M | 42 | 5 days 1X D | 4/22/2010 | 1 | Seasonal allergies | Extreme fatigue, restlessness, general anxiety, depression | Ironic that the latest Zyrtec commercials show allergy sufferers getting ready to go golfing and bicycling after taking the drug since just one dose left me beyond exhausted within an hour. i cannot over-emphasize how tired Zyrtec makes me feel; I knew something was wrong because I never sleep during the day but I felt myself drifting off while driving, reading, watching TV and working. I could tell that if I actually let myself fall asleep, it would be the kind of deep sleep that goes on for hours but leaves you feeling groggy and disoriented upon waking. I don't know too many people who can take 12 hours out of their day to sleep! Luckily I bought the box with five pills because I will never take this drug again. I would rather sneeze 100 times per day than ever feel this low again. | F | 30 | 5 days 10 mg 1X D | 5/8/2010 | 1 | chronic allergies | severe sedative effect. severe and sudden depression, increased vertigo ( spinning sensation and loss of balance). nightmeres almost of a halucinogenic nature. all of these symptoms stopped when i ceased takeing this drug, but it did take approximately 36 hours to feel significantly better. this is a dangerous drug and should be removed from the market by the FDA. the depression and sedative effects could become quite serious if a patient were not aware that that this drug was the cause. i happen to be very atuned to my body and the symptoms were so blatently obviously caused by this drug. however, someone who perhaps already suffers from depression may not be aware that this drug is causing symptoms, therefore, i state again: THE FDA SHOULD REMOVE THIS DRUG FROM THE MARKET COMPLETELY. | THE FDA SHOULD REMOVE THIS PRODUCT FROM THE MARKET COMPLETELY. | F | 54 | 5 days 10mg 1X D | 12/30/2012 | 5 | palpitations | no side effects except for a little tiredness. | I was having runs of palpitations for 2-4 hours at a time due to a leak in my roof leading to mustiness in my house. We were tested for mold, which I'm allergic to, and that was negative, but there is still mustiness in my home that is triggering this symptom. Benadryl did not take my palpitations away so my MD prescribed Zyrtec. I take 1 per day and have been symptom free since day one of the med. | F | 51 | 4 days | 11/24/2007 | 4 | allergies - mold dust | tiredness maybe higher blood pressure | does control my allergies as I have not felt this good for a long time never used allegra - i was very tired and then cut the dose in 1/2 and it improved a great deal | M | 50 | 4 days | 2/21/2006 | 4 | severe allergies | some depression, crying, agitation, bad dreams | It's been the most effective allergy medicine I've used. As soon as I started taking it I went from severe allergies to none at all. | F | 33 | 4 days | 1/5/2007 | 3 | asthma | Not exactly sure as my 11 month old is taking this. I think he has become more aggressive, but this could be attributed to him becoming a toddler. | M | 1 | 4 days | 9/30/2004 | 3 | Indoor and outdoor allergies | I would take the pill at night. I was so tired even at 2:00 the next day . I felt like a zombie and was having crazy and upsetting dreams all night. I did use a generic brand . I stopped cold turkey and I feel restless legs at night and headache. It definitely cured allergy symptoms , but is not worth the other feelings . | F | 46 | 4 days 10 mg | 8/17/2012 | 2 | hives | drowsiness, dizziness, headaches, moodiness/depression, increased appetite. | the first two days on this was fine, but lately have been noticing that i can't seem to get out of bed in the mornings. i feel drugged all the time. can't concentrate on anything and i found myself constantly snacking. i was just rolling around on the floor crying (because for some reason i couldn't understand anything in my fed courts book--now i know that reason is zyrtec), when i decided to google the side effects. glad i found this page and that i haven't lost my mind. will definitely stop taking it. hopefully, i won't itch because the itching does sound scary and i started on this drug to stop itching. | F | 26 | 4 days | 12/11/2005 | 2 | allergies which induced asthma | anxiety,inability to cope with frustration, not eating/excessive eating, fast emotional meltdowns, hives when missed dose, excessive thirst, now a kidney stone in a 7 yr old | My son is almost 8 and has been on this since age 4. We felt we had no choice as his allergies were contributing to emergency room level asthma episodes. It did help with that tremendously. But at what price? We have another child w/out allergies, very easy going. This little boy is very touchy emotionally, will rage over small things, has been in occupational therapy in school for 2 years for anxiety, etc etc.Will not eat for time periods and other times will eat excessively--not just "treats" but things like chicken cutlets. Also, having trouble concentrating on schoolwork, hard to read his writing. When we rarely forget to give it to him, he gets hives which we blame on allergies. Now he has a kidney stone, I have a bad feeling this may be related--has anyone else's child had this? I will be getting him off of this as safely and quickly as possible. | F | 43 | 4 days | 10/9/2007 | 2 | Allergies | When I slept on my right side I would dream that Bigfoot or chewbaca was watching me. When I would wake up I'd feel very drowsy and turn to my left side and dream a dinosaur or Godzilla was trying to swipe me with their tail. I would never take this medication. Also had sleep paralysis. | M | 40 | 4 days 5 1X D | 6/2/2010 | 2 | SEASONAL ALLERGIES | ESTREME FATIGUE - COULDN'T STAY AWAKE. WATER RETENTION | I WOULD RATHER HAVE THE ALLERGIES | F | 62 | 4 days 30 MG 1X D | 4/4/2011 | 2 | allergies | I felt tired and had a headache | F | 35 | 4 days | 3/14/2003 | 2 | Seasonal Allergies | I am super tired all the time, I took a nap the 2nd day for about 3 hrs and still felt lazy and tired afterwards. I get so hungry throughout the day. It helped very little as far as my dust/pollen allergies. Spring 2007 in MD. I still sneezed, runny nose, itchy eyes, etc after taking the pill. I took the pill at 8PM before I went to bed. After reading these comments I finally found the answer why i've been feeling/acting so differently. I knew it was the pill! Time to find a new allergy medicine. | I don't like it at all | M | 22 | 4 days | 5/3/2007 | 2 | severe itching | I've had horrible nightmares and freaky dreams, hallucinations, and severe drowsiness. I first time I took it, I took it right before bed and got to sleep about an hour later. I kept waking about every hour from these weird dreams that scared the crap out of me. I keep hearing noises in my room, I feel slightly dillusional and I can't keep myself awake. I would only recomend this if it's a last resort (which is the reason why I'm taking it) because you'd probably be better off without it! | F | 19 | 4 days | 10/27/2009 | 2 | allergies | mood swings, nightmares, not focus, sleeping problems. I am getting off!!!! | stay away from this drug!!! | M | 35 | 4 days | 9/2/2008 | 1 | Allergies | Extreme agitation, screaming, moody, hyper... | I chalked his hyper and out of control behavior on just being 3, but when my normally content and well behaved son turned "demonic" I started searching online to see if the zyrtec I have been giving him for almost a week had anything to do with it...seemed kinda strange that almost immediately the same day he started acting out and just being almost impossible to deal with!! I came across this site and read of other little ones that have the SAME side effects! I haven't given him a dose today and plan on throwing this crap out! Back to benedryl at night! | M | 3 | 4 days | 5/3/2009 | 1 | allergies | depression and lethargy -- no energy. | i take prozac for depression and allegra for allergies. the insurance company suggested that i try something else because allegra is so expensive. i sleep great but am in a depressive state. coffee doesn't help. so i know what's happened and am waiting this out until Zyrtec leaves my system. | F | 54 | 4 days | 9/11/2008 | 1 | seasonal allergies (e.g. pollen) | Drowsiness!!!! The drug relieves allergies, for sure, but at the cost of passing out 3-4 times a day from exhaustion. It also appears to cause slight heartburn. Won't take again. | M | 29 | 4 days | 6/11/2008 | 1 | Eczema, allergies | Out of character temper tantrums, throwing his body on the ground, inconsolability, severe frustration and crying attacks, fatigue, and difficulty waking in the morning. | We will stop use of this drug immediately and go back to Benadryl. | M | 4 | 4 days | 5/23/2008 | 1 | rhinitis from eye medication | Amnesia and confusion. I suddenly became aware I was driving on the wrong side of the median on a narrow road. I could not remember how i came to be there. I had lost about three minutes or four minutes of time. | This was exceedingly scary. It took a lot of research and reading of fine print on medical websites to isolate Zyrtec as the only thing I was taking that could have been responsible for this period of amnesia. | F | 66 | 4 days | 6/21/2008 | 1 | seasonal allergies | Lethargy, sleeplessness, high blood pressure, irregular heart beat. | I started taking this drug because I was out of my normal presecription (Allegra) and I was travelling out of town. The result was a difficult few days as I tried to stay focused during meetings with little sleep the night before. The headaches and flushed feeling were constant. Upon returning home I took my blood pressure and it was through the roof. I would look carefully at your condition before considering taking this drug. | M | 56 | 4 days | 6/28/2008 | 1 | allergies | With in two days of use I was very testy, disinterested in my relationship with my wife, on edge, and full of anxiety. The smallest things set me off. I had difficulty sleeping with horrific violent dreams. I quit taking ZYRTEC and within 3 days I was my old self. | M | 51 | 4 days | 3/31/2009 | 1 | Sons allergies | I have a 4 yr old and a 2 yr old. They both are having bad side effects. I thought I was going mad until I started researching the drug a bit more. My oldest itches all over, mostly on the back and stomach. He is normally a very good boy, listens well, and follows directions. Lately he's been having temper tantrum melt downs over the littlest things. Which is not normal for him at all. My youngest has been the worst. He will not sleep at night. Crying spells can last 2-3 hrs with 30 min breaks of sleep in between all night long. He sleeps very sound in the afternoon for naps. He is much more irritable, and has more temper tantrums than normal. I'm taking my children off this drug for good. I wish the Physician would have explained the possible side effects before perscribing. | F | 30 | 4 days | 3/19/2009 | 1 | allergies | Almost immediately experienced extreme irritability and a racing pounding heart. | I tried taking Zyrtec two different times; when it was prescription only and when it came out OTC. Both times I had the same experience. At first I felt very irritable and foggy headed then after a day or two began to have an extreme pounding racing heart. You could see my pulse beating in my neck and I felt as if I was going to have a heart attack or something. I really can't believe that this medication is available over the counter. I see others have experienced the same thing. | M | 45 | 4 days | 4/13/2009 | 1 | Coughing from post-nasal drip | I gave my 5 1/2 yr old son this medication and within a day he was moody and miserable. I didn't immediately connect it with the medicine, I just thought he wasn't feeling well. I gave it to him for about 4 days and also started my 8 yr old on it when he started with a similiar cold. They were at each others throats, fighting and generally irritable. I stopped the medicine for both of them and it took about 2 days for them to be back to normal. What a drastic reaction they both had. I will never give it to them again. | M | 5 | 4 days | 4/24/2009 | 1 | possible allergies, skin issues | extreme behavioral disorder (3 yr old) "possessed" | I have the world's sweetest 3 year old... until we had him on Zyrtec for four days. He woke up last night at midnight with uncontrollable energy. He fought with us, looking at us like he'd never seen us before, thrashing about, crying wildly and screaming. After about an hour, he finally went to sleep. This morning he was an angel again, and the Zyrtec is going in the trash. DON'T BUY OR USE. | M | 3 | 4 days | 5/28/2009 | 1 | Seasonal allergies | My son became very fussy, woke up crying from naps and sleep, threw tantrums for no reason, started banging his head on hard objects. His speech dropped off and he stopped being his usual happy, affectionate self. | M | 2 | 4 days | 5/26/2009 | 1 | To clear nasal passages, hay fever | Itching all over body, esp arms and legs and face. Lethargy and slight loss of mental focus. Very uncomfortable. Will never use it again. | M | 56 | 4 days | 10/8/2008 | 1 | seasonal allergies | I started taking zrytec and only had runny nose tried to stop after a year and experience hives which I never had before and am force to continue to take it or suffer I am in worse shape than when I started out drys out my skin and mouth and eyes quitting taking this medicine is worst than when I stopped smoking it is addictive and I was never told that | F | 35 | 4 days | 8/10/2004 |