Summary: Antihistamines are effective medications that remain central to the treatment of the most common allergic diseases, including allergic rhinitis and chronic urticaria. First-generation antihistamines show poor H1-receptor selectivity and cross the blood-brain barrier easily, which may cause sedation and compromise performance at school or work, and heavily impair mechanical vehicle driving capability.
Additionally, they have anti-muscarinic, anti-adrenergic and anti-serotonin activity, therefore they are not presently recommended for standard use. In contrast, second-generation H1-antihistamines are highly selective to the H1 histamine receptor, minimally cross the blood-brain barrier and have much fewer side effects. However, not all second-generation antihistamines have the same safety profile.
When choosing the right medication, several factors should be taken into consideration, including cardiotoxicity, pharmacokinetics, drug interactions, sedative effects and safety in children and the elderly.
Unfortunately, due to low price, limited knowledge among patients and general practitioners and over-the-counter availability, old-generation antihistamines with severe adverse effects are still widely used. Out of all allergy medications available on the Polish market, bilastine appears to have the most favorable safety profile, with clinical trials confirming that it is safe to use in daily doses of up to four times the standard quantity.