I strongly suggest he try some of the alternatives to medication! They work... very well. I was on medication for 10 years, until it stopped working and I was forced to look at other options... I wish I had looked for alternatives years ago, because unlike the medication they actually help you work out what is going on emotionally and resolve it. The medication makes you feel a bit better without really dealing with the underlying issues...if you aren't careful, you'll be on it for the rest of your life.
DO NOT go to a psychiatrist. They will basically put you on drugs, and that's it. Look for a talk therapist with an EMDR certification or one works with other cutting edge stuff:
1. EMDR. This is a form of therapy that uses technology to put the patient into a deeply relaxed state for talk therapy. It is especially useful for people who have had bad experiences in their past, even as far back as childhood. It was first used for soldiers, police, and firemen with PTSD, but it is now used for all kinds of things. A nine month course of EMDR put my extremely severe clinical depression (I was suicidal and anorexic) into remission--and I felt substantially better after the first two sessions. It seems to have permanently banished my social anxiety, and my depression is still in remission two years later. Lots of good research on this method.
2. Sound and light therapy. This is another technology-aided relaxation therapy, used at home. You can order a machine from Amazon.com and experiment on your own (I happen to have the "Proteus"), or, possibly better, look for a therapist who will coach you in exactly how to use the machine best. The machine will come pre-programmed with all kinds of routines, for everything from exam performance, to help sleeping, to routines that are good for ADD, anxiety, and depression. Again, lots of research support.
For a depressed person, working with a therapist is a good idea at first... some of the routines might conceivably make it worse. My 5 year old son uses a machine to help ease his anxiety, and we were instructed to avoid the routines designed for kids with ADD... they would make his anxiety more intense. We experimented once with a routine designed for kids with autism... and let's just say that he had a very strange day.
3. Exercise. But it has to be quite a lot. More studies support this.
4. Make sure your husband is getting enough sleep. Sleep deprivation can be a major driver of depression. If he has trouble sleeping, a sound and light machine can help a lot.
5. A final long shot--not backed by clinical studies, but maybe worth a try--is the ideas of a researcher Seth Roberts, who came up with a theory called "Faces in the morning." His theory was that for thousands of years, the first thing people would see when they got up was other people's faces... lots of them, as they planned to hunt for mammoths or whatever. So he started watching TV shows in the morning, talk shows with BIG images of faces. He found that it improved his energy levels, mood, and made it easier to sleep in the evening. I've been experimenting with it myself, and it does seem to make a difference. (by contrast, seeing faces in the evening was not such a good idea).
Good luck.