Thanks for asking at Healthcare Magic. I read your question and I understand your concern. Monteka LC is levocetrizine an antihistamine H1 blocker second generation. Many clinical trials both 4 weeks and 6 months have established its in both adults and pediatric group. The only concern are its immediate side effects that is allergic reactions, anaphylaxis, angioedema, urticaria, hives. All that you have to do is to vaccinate him with both influenza vaccine and pneumococcal vaccine to prevents allergic reactions. Avoid pollens, dust, dust mites, aspirin. Take your best care. Don t forget to rate this answer and close the discussion at Healthcare Magic. Regards Dr Ejaz