Is it permissible to sign papers to discontinue "Prostin" medication for an infant who is kept alive by it, due to the high cost of intensive care and the inability to provide treatment in specialized hospitals that require a royal decree?

If the purpose of signing the papers is for the treatment of the son in the aforementioned centers, and the person is eligible for that, then there is no harm in signing. In other cases, efforts must be made to treat him by whatever means possible.