Is it normal to get sick after tonsillectomy / adenoidectomy?

Not usually: Most adults feel poorly for 10-14 days after tonsillectomy and that is normal. The throat typically looks nasty during that period and a low grade fever often accompanies mild dehydration. Drinking lots of fluids will help, but until you are eating better, the recovery is slow. Force fluids and advance your diet to feel better. Sometimes gentle warm salt water gargling can help as well.