<unk>  is known to occur with frequent use of many different<unk> s, including most commonly: triptans, ergotamines, simple and combination analgesics, and opioids. Dietary and medicinal caffeine consumption appears to be a modest risk factor for chronic daily headache onset, regardless of headache type.<unk>  is very rare in patients without a history of recurrent headaches, and it rarely develops in patients who take analgesics for non-headache pain, like arthritis or irritated bowels. Furthermore,<unk>  is more probable when a family history of<unk>  is present, thus indicating a genetical susceptibility. It is thought that rebound headaches are caused by a neuronal re-adjustment process. Analgesic intake raises the pain threshold. Thus, lacking pain stimuli for longer times, the brain re-calibrates to experience normal stimuli as pain. The underlying mechanisms that lead to the development of the condition are still widely unknown and clarification of their role is hampered by a lack of experimental research or suitable animal models. Various pathophysiological abnormalities have been reported and they seem to have an important role in initiating and maintaining chronic headache (genetic disposition, receptor and enzyme physiology and regulation, psychological and behavioural factors, physical dependencies, recent functional imaging results). Headache treatment Opioids and butalbital are sometimes inappropriately used as treatment for migraine and headache and should be avoided in favor of more effective, migraine-specific treatments. Opioid and butalbital use can worsen headaches and cause<unk> . When a patient fails to respond to other treatment or migraine specific treatment is unavailable, then opioids may be used. Regular use of over-the-counter drugs (OTC) such as paracetamol and NSAIDs can also be a cause of<unk> . OTC<unk>  for headache should be limited to use for not more than two days weekly. Concurrent with<unk> ,<unk>  of acetaminophen (known as paracetamol in some countries) for treating headaches risks causing liver damage and NSAID<unk>  can cause gastrointestinal bleeding.
Medication overuse headache
Lupus headache
Vascular headache
Cluster headache
Cervicogenic headache
External compression headache
Cold-stimulus headache
Red wine headache