first night on biaxin, had increased heart rate, 100 resting. I woke up in the middle of night last night with severe metallic taste in my mouth, checked web for metallic taste in mouth and this web site came up for side effects of this medication, how strange.Felt better yesterday.T his is my 3rd day on, so wondering what is next. I guess its better than the infection, but I wonder if I should change after reading other comments.