Antihistamines knocking me out suddenly?

[Usernameunavailabl]

I sometimes get a sort of prickly heat reaction of some kind if I eat anything with too much paprika in it I've realised over the last few years. I get really itchy hands, feet, nose, ears, boobs and vag (extremities).

I had some M&S tomato ketchup with a few chicken strips for lunch yesterday without realising there was paprika in it and omg within 10 mins I was riving at my hands and so took a cetirizine tablet around 2.30pm and have literally just woke up on sofa at 4.10am. I didn't feel drowsy/woozy or anything just generally noddy (not unusual for a Sunday afternoon for me) and so snuggled up on sofa with blanket for a snooze.

Similar thing happened last Tuesday when I last had cetirizine when I've thought about it.
I took one after lunch, felt knackered all afternoon at work and had thought was just too much carbs from jacket spud I'd had. Finished work at 5.00pm nodded on sofa from around 5.30 till 8.00pm pottered around in a daze for half an hour or so and went to bed at 9.00pm and slept through till my alarm at 6.50am.

Aibu to think I'm suddenly having an alternative response to the antihistamines? I've taken them for years. Always OTC generic cetirizine (usually just the cheapest) but I've never had this before.

Anyone else had this happen?

I don’t have an answer for you but the same thing happened to me recently. I have taken piriton for hay fever in the past, amongst other things. Recently, I have been having random allergy like reactions to cleaning products - when I took piriton last week for this, I had to leave work lay down and sleep for five hours. Completely knocked me out!

I’m wondering if it’s actually an allergy response rather than the medicine itself. I know when I took my daughter to the allergy clinic they said don’t give her piriton because it can mask the symptoms of secondary anaphylaxis (which are sleepiness and passing out 🫤). I maybe should have taken this advice myself.

My doctor once told me piriton and the like antihistamines can be used as unofficial sleeping pills so I think it's a common side effect

Cetirizine is a non-drowsy antihistamine isnt it? Same as loratidine. So I reckon you’re just tired? Also, if I was getting a reaction like that, I’d be taking something a bit better like a chlorphenamine or a fexofenadine.

Have your allergies become more severe? Some antihistamines can cause sleepiness but would be unusual for one you ve always used to just start having that effect. Histamine response/allergic reaction can cause sleepiness too

Seeing as Nytol is actually an antihistamine I'm not sure why you think this is a surprise, it's a known side effect. You could try a different one and hope it doesn't have the same impact on you personally?

Agreed, I'd be getting something like Telfast (fexofenadine) for a reaction that causes that level of irritation that quickly

I was given Cetirizine by my GP for urticaria and it made me really drowsy. My GP said that some people can have a drowsy reaction to a non-drowsy antihistamine. I take loratadine and don't have the same issue.

Cetirizine isn't one of the drowsy causing group of antihistamines though so yes it would be unusual for it to be the cause of the sleepiness

Exactly the same happens to me.

Same happens me after cetrezine. I took it one night and woke up the next morning 3 hours later than my normal wake up time and even then had to drink coffee to stop the drowsy feeling. I don't normally drink coffee! I used to give it to my child in the mornings for hay-fever but stopped after realising the effect it had on me.

I can only take loratadine as the others make me tired.

Citirizine has always made me sleepy, I take it if I ever need help sleeping. I was recently advised to take it for an elegiac reaction and as it is one a day, took it at night.

Had the same thing happen to me. I took cetirizine for years for hay fever with no problems - all the way through professional exams etc and was never drowsy. Then one year it just started wiping me out completely. I tried taking it in the evening but still felt like I was wading through treacle all the following day. It was definitely the pills and not just tiredness (don’t think I’ve ever been more exhausted than when working full time and studying).

I now take fexofenadine which is great, I have read it’s the one recommended for pilots etc and other safety critical roles so a lot less likely to make you drowsy.

I would love it if I could get very drowsy on cetirizine. I never feel any different on any antihistamine.

Ceterizine is meant to be non drowsy but always knocks me out, my partner too but my kids take it no problem. Apparently 1/10 react the same.