Hello dear,
I am getting it like your husband had this single episode of
dizziness and as you mentioned that it improved once he went back to bed, it appears to be somehow related to posture.It may be an episode of
postural hypotension or syncope.Cardinal features in an episode of syncope are premonitory symptoms of palpitations,
excessive sweating and paleness on face just before the episode.Characteristically,patient with syncope have a transient
loss of consciousness,for a few seconds following which he regains consciousness.
Another differential to think of in this case can be of an atypical form of seizure,but that is a remote possibility.Was this dizziness associated with sudden neck flexion or extension or lateral flexion?If yes,possibility of a benign vertigo can be considered.Is your husband having any ear problems like ringing in the ears,hearing loss?If yes,this may be associated with such an episode.Is your husband a diabetic?Diabetics may have autonomic dysfunction,which may cause this.Some drugs can also cause this type of problem.Please visit a
neurologist,he may examine and take detail history and do simple firstline tests like screening for hypotension with postural drop.He will definitely be of help.Please ask further if you feel so.