Note: the following terms are to be considered equivalent to intractable: pharmacoresistant (pharmacologically resistant), treatment resistant, refractory (medically) and poorly controlled Use additional code for adverse effect, if applicable, to identify drug (T36-T50 with fifth or sixth character 5) Excludes1: headache NOS (R51) lower half migraine (G44.00) Excludes2: headache syndromes (G44.-)
