What can my husband take for headaches if allergic to Asprin?

There are many pain-killers which do not contain aspirin such as paracetamol (sold as Calpol), Diclomol (diclofenac with paracetamol), Proxyvon, ibuprofen (sold as Brufen etc.). Please keep in mind that sometimes patients develop cross-allergy i.e. people allergic to aspirin are also allergic to other pain-killers and therefore, one needs to try out different medicines.