Chronic headache is most often associated with drug abuse and medication overuse headache (MOH) is the main complication of migraine disease results in chronic daily headache. The first phase of treatment consists of drug withdrawal .

The second phase of treatment (called consolidation) is to maintain the balance: treating headaches and reducing / stopping the drug use.

The aim of this study is

1. verify the feasibility of a home withdrawal treatment with normobaric oxygen therapy (NOT) delivery by high flow concentrator
2. use normobaric oxygen therapy (NOT) as a therapeutic measure to treat headache through withdrawal period.

It is a feasibility pilot study in chronic headache with or without medication-overuse. All patients receive a care for outpatient withdrawal that involves sudden stop drug abuse and used to be called "traditional management". The subsequent attacks will be treated with NOT from a high-flow concentrator

Primary endpoint. Feasibility study of treatment with NOT evaluated by the percentage of patients who accepted NOT during the withdrawal phase then to treat attacks.

Secondary endpoints. Efficacy will be assessed by the percentage of patients having no chronic headaches two months after the start of withdrawal (less than 15 days of headache per month) and no longer in drug abuse (less than 10 days per month with drug intake).

Visits V1 (first visit) Inclusion V2 at one month V3 at 3 months V4 (last vist) at 6 months

Effective : 30 patients

Inclusion Criteria:

• Migrainous according to the criteria of the International Headache Society
• Medication-overuse headaches according of the International Headache Society
• No prophylaxis treatment or same prophylaxis treatment from more than one month
• Signed informed consent

Exclusion Criteria:

• Pregnancy
• One or more failed withdrawal treatment
• analgesic treatment for another reason than headache
• Contraindication of normobaric oxygen therapy
• Contraindication of ketoprofen (rescue therapy)