My 96 year old father-in-law has been on coumadin for about 10 years.  He has developed osteoarthritis.  He refuses to go outside into the sunshine anymore.  Is there any reason he shouldnt while taking coumadin?  Does he even need to continue taking it at his age?
Unless one has some serious side effects, coumadin may be continued if prescribed for any reason by his doctor. There is no known bad effects of sunlight, and it may be due to photophobia from other causes. So an opinion with eye specialist may be indicated.