Chronic intractable headache unspecified icd 10 July 8, 2019 16 32 64 128 Chronic non intractable headache unspecified icd 10 Icd 10 code for chronic intractable headache unspecified headache type Chronic headache icd 10 Intractable headache icd 10 Icd 10 code for chronic tension headache not intractable