If the child took Rupafin, now uses Contrahist, if he returns to Rupafin, will it be ineffective?

There are no contraindications to continue rupafin therapy after treatment with Contrahist. The fact that Rupafin belongs to the second generation antihistamines, and Contahist to the third generation means, for example, that Contrahist causes fewer side effects (m.in does not put you to sleep). It does not mean, however, that after its use Rupafin will be ineffective. The response to Rupafin treatment will be similar to what it has been so far. I enclose a link to our article, which may be helpful: https://www.gdziepolek.pl/artykuly/leki-przeciwhistaminowe Rupafin is only available on prescription. Here you can check the availability of the drug in pharmacies and make a reservation: contrahist https://www.gdziepolek.pl/produkty/68239/rupafin-tabletki/apteki in 10-tablet packages can be purchased without a prescription. Here you can check the prices of the drug and order the drug with home delivery or collection at the pharmacy: https://www.gdziepolek.pl/produkty/19716/contrahist-allergy-tabletki-powlekane/apteki