Shafaqna (International Shia News Agency) – Ayatollah Khamenei answered a question regarding donating blood to non-Muslims . According to Shafaqna the question and answer are as follows:
Q: Being Muslim, are we allowed in the month of Muḥarram to donate blood in non-Muslims’ hospitals?
Knowing that blood will go to the People of the book who are mostly Christians. Is this act mustaḥabb?
A: By itself, there is no objection to that. Rather, it is recommended by shar‘ in certain circumstances.