Culture shock is something that I believe every missionary deals with at one point or another to one degree or another. Personally I would say that culture shock has not been such a big issue for me but from other missionaries I know personally and that I know about it can be a big problem.
There are different symptoms of culture shock such as feeling sad and lonely, insecurity, irritability, and resentment, as well as idolizing the culture and environment you came from as opposed to where you live now. Reverse culture shock can be harder to deal with because people often have an unrealistic recollection of where they came from and once they return their image and reality clash dramatically. There are different stages of culture shock ranging from the initial excitement of being in a new place to the final adjustment of learning to live and thrive in the new environment.
Is there a "cure" for culture shock? While I am certain no one would consider me an expert on culture shock I have lived outside of my home country for over 10 years. I realize that no place is perfect and there will always be some things that I would rather see done differently; that goes for Germany and the USA. Many people spend their time thinking and talking about how great it is somewhere else and why their current location is not as good. That and always longing for some type of food or dwelling on how little they may be able to see some family and friends is, in my opinion, a recipe for disaster. Every place and every people group have their positives and their negatives. Culture shock may be something that has to be dealt with but I believe that being flexible and keeping the right attitude are keys to not allowing culture shock to become a personal crisis.