I agree with your plan to finish out the year. I know it sucks, but in my experience people tend to respect you more if you finish what you started...unless you have somewhere else to "jump" (i.e. some off cycle spot to start next spring in another specialty) I would hesitate to tell you it's OK to quit at this point, unless you are just so totally miserable that you feel you're going to have a melt down and can't hack it even for another 7 months. Again, I know it sucks, but if the alternative is having no paycheck and perhaps not good letters of evaluation from your current program (as they may get mad if you quit halfway through the year) then staying where you are while you plot your next move may be the wisest thing. If you bail at the end of the year, having given them several months notice, I don't think there will be much in the way of fallout...people bail from surgical residencies all the time and it really isn't that unusual.
Also, realize that the next few months are going to be tough, since in a lot of parts of the country it's cold and dark and you have figured out by this point in the year that interns are scut monkeys, particularly in surgery, and the work is hard and long. However, also realize that as the year goes on you get more and more efficient at doing intern stuff, and so it may get a little less frustrating for you. Also, if you know that you are leaving @the end of the year, you don't have to be quite so much of a gunner and maybe can stress less about what some attendings think of you. You definitely don't want to get a reputation as a slacker, or for not knowing what you are doing, so still maintain a professional demeanor and do all your work and it doesn't hurt to suck up a little to attendings when you get the chance.
I wouldn't favor telling anyone at your current program you are thinking of leaving. If you think you can trust them not to blab to your current program's attendings, then getting advice from med school mentor(s) might be helpful (that is if you're @ a different institution from where you did med school).
Actually, r.e. one of the comments above, I actually don't think the med student's advice was that bad, given he/she is a student. I do not think that the OP will have time to go on interviews for another specialty while he/she is a surgical intern, though. The only time he/she could do it is during vacation time, and unlikely the scheduling will work out. He/she could still potentially apply to something like intenal medicine even this late in the year (probably could still apply in early November), but he/she would need to have at least 1 letter from someone in that specialty, and 2 would be preferable. I don't favor applying to something else out of desperation, though, as it's important to be happy with one's future career. It would be better to take a research year or do an MPH next year or something, or try to get an off-cycle spot for PGY2 that starts next year (like anesthesiology) than to just take any random spot you can get right now (likely would be fp or IM, maybe peds, if it starts mid-year this year).
I am curious whether the OP is signed up for 5 years of general surgery or something else. If he/she just decided that surgery is all wrong, then by all means make plans to quit. However, if doing something like urology and it's being a scut monkey general surgery intern that is driving the OP crazy, then he/she might want to think twice. Being an upper level resident in something like ENT or urology will be quite different than being a surgical intern. If it's the general lifestyle, most of the attendings and other trainees' personalities, or the surgery itself that doesn't mesh with you any more, then getting out might be the best choice.
I also see nothing wrong w/trying an SSRI. I rx'ed them lots of times as an internist and they have a good safety profile and many people find them helpful.
