| G44 | Other headache syndromes |
| | Cluster headaches and other trigeminal autonomic cephalgias (TAC) |
| | Cluster headache syndrome, unspecified |
| | Cluster headache syndrome, unspecified, intractable |
| | Cluster headache syndrome, unspecified, not intractable |
| | Episodic cluster headache |
| | Episodic cluster headache, intractable |
| | Episodic cluster headache, not intractable |
| | Chronic cluster headache |
| | Chronic cluster headache, intractable |
| | Chronic cluster headache, not intractable |
| | Episodic paroxysmal hemicrania |
| | Episodic paroxysmal hemicrania, intractable |
| | Episodic paroxysmal hemicrania, not intractable |
| | Chronic paroxysmal hemicrania |
| | Chronic paroxysmal hemicrania, intractable |
| | Chronic paroxysmal hemicrania, not intractable |
| | Short lasting unilateral neuralgiform headache with conjunctival injection and tearing (SUNCT) |
| | Short lasting unilateral neuralgiform headache with conjunctival injection and tearing (SUNCT), intractable |
| | Short lasting unilateral neuralgiform headache with conjunctival injection and tearing (SUNCT), not intractable |
| | Other trigeminal autonomic cephalgias (TAC) |
| | Other trigeminal autonomic cephalgias (TAC), intractable |
| | Other trigeminal autonomic cephalgias (TAC), not intractable |
| | Vascular headache, not elsewhere classified |
| | Tension-type headache |
| | Tension-type headache, unspecified |
| | Tension-type headache, unspecified, intractable |
| | Tension-type headache, unspecified, not intractable |
| | Episodic tension-type headache |
| | Episodic tension-type headache, intractable |
| | Episodic tension-type headache, not intractable |
| | Chronic tension-type headache |
| | Chronic tension-type headache, intractable |
| | Chronic tension-type headache, not intractable |
| | Post-traumatic headache |
| | Post-traumatic headache, unspecified |
| | Post-traumatic headache, unspecified, intractable |
| | Post-traumatic headache, unspecified, not intractable |
| | Acute post-traumatic headache |
| | Acute post-traumatic headache, intractable |
| | Acute post-traumatic headache, not intractable |
| | Chronic post-traumatic headache |
| | Chronic post-traumatic headache, intractable |
| | Chronic post-traumatic headache, not intractable |
| | Drug-induced headache, not elsewhere classified |
| | Drug-induced headache, not elsewhere classified, not intractable |
| | Drug-induced headache, not elsewhere classified, intractable |
| | Complicated headache syndromes |
| | Hemicrania continua |
| | New daily persistent headache (NDPH) |
| | Primary thunderclap headache |
| | Other complicated headache syndrome |
| | Other specified headache syndromes |
| | Hypnic headache |
| | Headache associated with sexual activity |
| | Primary cough headache |
| | Primary exertional headache |
| | Primary stabbing headache |
| | Cervicogenic headache |
| | Other headache syndrome |
