These two allergy drugs produce very similar results. Both cetirizine and loratadine are nonsedating antihistamines.They both calm your immune system’s reaction to allergens. They also take effect at different times and stay effective for different durations. Antihistamines have a reputation of making you sleepy because the first types crossed into your central nervous system more easily and had a direct effect on your alertness. Now take a deep breath and feel the Allegra-D difference. One pill combines a non-drowsy antihistamine with a powerful decongestant giving you fast,* allergy and congestion relief for up to 24 hours.The manufacturers claim it to be more effective with fewer side effects than previous second-generation drugs; however, there have been no published studies supporting this assertion.A study part-funded by the manufacturer UCB concluded it may be more effective than some other second- and third-generation anti-histamines, but did not compare it to cetirizine.There might be a problem taking some herbal remedies and supplements alongside loratadine - especially ones that cause sleepiness, a dry mouth or make it difficult to pee.
It does not prevent the actual release of histamine from mast cells.Levocetirizine is called a non-sedating antihistamine as it does not enter the brain in significant amounts, and is therefore unlikely to cause drowsiness.However, some people may experience some slight sleepiness, headache, mouth dryness, lightheadedness, vision problems (mainly blurred vision), palpitations and fatigue.Two years later it went away, as well as my blepharitis at the same time. Anyway, having researched on the 'net for a while, I figured it could be rosacea or seb.dermatitis, so I went out and bought several products including a 1% hydrocortisone cream, aloe vera gels/washes, Nizoral and Emu Oil.