From Longman Dictionary of Contemporary Englishpainkillingpain‧kill‧ing /ˈpeɪnˌkɪlɪŋ/ adjective [only before noun] able to reduce or remove pain painkilling drugs
Examples from the Corpus
painkilling• I couldn't be certain how much painkilling medication she had taken, but it was almost certainly not enough.• Half the active substances used for rheumatic conditions also appear in the 100 or so painkilling preparations available.• The judge also ruled that medical staff could administer a painkilling sedative to assist him in the process. 