Figure 2:

Circadian rhythms in headaches and neuropathic pain. Headache disorders, including cluster headache, migraine and hypnic headache, and neuropathic pain display circadian rhythmicity of attack occurrence. Several clock components have also been implicated in these diseases in either rodent models or in small human studies. Note that Nr1d1 encodes REV-ERBα. Several pain medicines, such as lithium, valproic acid and melatonin and corticoids, are known to reset the circadian clock.