Is it that warfarin stuff Celine. I think he/you need to get some kind of professional advice as to if its safe to fly. It does seem early stages in his condition. My other half had warfarin via injection for about 3 months, and he flys now. He had a suspected clot but it was just after we had returned from a holiday, not just prior to going.
They may let him fly, but he may possibly need a 'fit to fly' certificate.
From what I remember (2002) though my hubby was kind of wedded to the hospital for the three months that he was on it. He had to keep going up there to have the thickness/thinness of his bood monitored. This was in London and the clinic was on every afternoon from 1pm to 4pm and it was stranding room only every-time, it was a real eyeopener as we didn't realise so many were taking it