Sneezing, coughing and hiccups. These are things that musicians may discuss among themselves but are usually not mentioned in books on how to play. Even though learning to deal with involuntary burps and coughs is vital for all wind players. (All the 10-year-olds out there will love knowing that you can usually play right through a belch, making them the least of your worries.)
The overall advice is actually very simple: play till you can’t, don’t lose the beat and go right back to playing as soon as you can. This works fine for simple dry sneezes but if you play outside and have ragweed allergies, keep a handkerchief in easy reach and be prepared to deal with missing a few notes or even a phrase. All the “ah-ah-ah” parts of the sneeze can usually still be played through although your tone may not be its best. The “choo” part will interrupt you, no way around that, so be ready to jump back in right after that last blast.
Hiccups are trickier. There is next to nothing you can do to reduce the impact they have on your breath and playing. All you can do is keep a steady beat, keep going and joke with the audience about the “rests” you added. There is a silver lining, at least for me. Something about how I breathe while playing usually prevents the hiccups from happening at all or cures them better than all the folk cures about water and surprises. For some odd reason, I can only make this work when I am actually playing the flute though. Just breathing the way I do while playing when I have the hiccups doesn’t help in everyday situations. Ah well.
Coughing. I saved the worst for last. Coughing is a problem because the more I suppress a cough, the worse the need to cough gets and the longer I will have to cough once I start. Suppressing a cough can also lead to tears running down my face which is quite distracting for all concerned. Another problem is that waiting to cough till a rest may mean I am coughing during another performer's solo, a big no-no. So if I have a rest coming up (soon!) that is not quiet or the piece is nearly over, I will try to suppress the cough till then but otherwise, it is better to stop playing and cough right away. The interruption is usually shorter and less severe.
One last tip is to keep a little water nearby for sipping cures of hiccups and soothing of the throat after coughing or sneezing. Other than that, all you can do is keep calm and play on.