irritate

verb

1. cause annoyance in; disturb, especially by minor irritations"Mosquitoes buzzing in my ear really bothers me"
2. excite to an abnormal condition, or chafe or inflame"Aspirin irritates my stomach"
3. excite to some characteristic action or condition, such as motion, contraction, or nervous impulse, by the application of a stimulus"irritate the glands of a leaf"