24 hour relief.
I've never bothered getting anti-histamines for my "summer cold" as while annoying, it was manageable. A few years ago, I suddenly developed an allergic reaction to dog saliva. The itch on my arms was so unbearable, that I was scratching myself raw and bleeding.
Cetirizine hydrochloride (particularly from Galpharm) saved the day. My dogs can still sleep on my bed, my hayfever is practically non-existent, and an unexplained itchy scalp that I had been scratching for years has also been sorted.
About 25-26 hours after the last dose, I will often find myself scratching my inner wrists, as the anti-histamine loses potency. Some other brands available on ebay and Amazon which claim to have the same active ingredients are completely ineffective; whether they are fake or have a less efficient excipient, I don't know.
Galpharm Cetirizine HCl provides a blessed relief.
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