1. The use of diaminoxidase (DAO) to obtain a composition for the prevention or treatment of fibromyalgia or chronic fatigue syndrome. 2. The use according to claim 1, characterized in that the DAO is administered orally in the form of tablets, capsules or sachets. The use according to claim 1, characterized in that the DAO is administered in a dose of from 0.1 to 50 mg. The use according to claim 2, characterized in that the DAO is administered in a dose of from 0.1 to 50 mg. The use according to any one of claims 1 to 4, characterized in that said composition further comprises caffeine. The use according to claim 5, characterized in that the caffeine is administered in a dose of from 1 to 100 mg. The use according to any one of claims 1 to 4 or 6, characterized in that said dosage forms are protected from the effects of the stomach environment. The use according to claim 5, characterized in that said dosage forms are protected from the effects of the stomach environment. The use according to any one of claims 1 to 4, 6 or 8, characterized in that the DAO is used in free form, in the form of a powder, lyophilized powder, microcapsules, nanocapsules or liposomes. 10. The use according to claim 5, characterized in that the DAO is used in free form, in the form of a powder, lyophilized powder, microcapsules, nanocapsules or liposomes. The use according to claim 7, characterized in that the DAO is used in free form, in the form of a powder, lyophilized powder, microcapsules, nanocapsules or liposomes.1. Применение диаминоксидазы (ДАО) для получения композиции для предотвращения или лечения фибромиалгии или синдрома хронической усталости.2. Применение по п.1, отличающееся тем, что ДАО вводят перорально в форме таблеток, капсул или саше.3. Применение по п.1, отличающееся тем, что ДАО вводят в дозе от 0,1 до 50 мг.4. Применение по п.2, отличающееся тем, что ДАО вводят в дозе от 0,1 до 50 мг.5. Применение по любому из пп.1-4, отличающееся тем, что указанная композиция допо
