1. because he is taking Coumadin (warfarin), thus could be reason of his psychosis (confused & not co-operating) and moreover it is Contra indicated in old Age, thus talk with your Doctor regarding it.
2. gravol (dimenhydrinate) is usually given for nausea and vertigo caused by Meniere's disease and not to induce sleep, again consult with your Doctor.
3. hoarseness of voice with cough,as seen in general practice is commonly due to Throat infection
or laryngeal inflammation
BUT if voice doesn't become Normal, seek opinion of ENT surgeon for Laryngoscopy
ans simultaneously go for X-ray chest and Thyroid profile.
4. If he is not co operating it may be due to the confusion arising due to DRUG or because of Dehydration
and fallen B.P.