1. Diaminoxidase (DAO) for use in the treatment or prevention of attention deficit hyperactivity disorder (ADHD) .2. Diaminoxidase for use according to claim 1, wherein the DAO is administered orally in the form of tablets, capsules or sachets. 3. Diaminoxidase for use according to claim 1, wherein the DAO is administered in doses of 0.1 to 50 mg. Diaminoxidase for use according to claim 2, wherein the DAO is administered in doses of 0.1 to 50 mg. Diaminoxidase for use according to claim 1, wherein said dosage forms further comprise caffeine. Diaminoxidase for use according to claim 2, wherein said dosage forms further comprise caffeine. Diaminoxidase for use according to claim 3, wherein said dosage forms further comprise caffeine. Diaminoxidase for use according to claim 4, wherein said dosage forms further comprise caffeine. Diaminoxidase for use according to claim 5, wherein caffeine is administered in doses of 1 to 100 mg. Diaminoxidase for use according to claim 6, wherein caffeine is administered in doses of 1 to 100 mg. Diaminoxidase for use according to claim 7, wherein caffeine is administered in doses of 1 to 100 mg. Diaminoxidase for use according to claim 8, wherein caffeine is administered in doses of 1 to 100 mg. Diaminoxidase for use in PP. 1-12, where these dosage forms are protected from digestion by gastric juice. 14. Diaminoxidase for use in PP. 1-12, where DAO is used in free form, in the form of a powder, lyophilized powder, microcapsules, nanocapsules or liposomes. 15. The diaminoxidase for use according to claim 14, wherein the DAO is used in free form, in the form of a powder, lyophilized powder, microcapsules, nanocapsules or liposomes. A composition comprising diaminoxidase for use according to any one of claims. 1-15.1. Диаминоксидаза (ДАО) для применения в лечении или предупреждении синдрома дефицита внимания с гиперактивностью (СДВГ).2. Диаминоксидаза для применения по п. 1, где ДАО вводят перорально в форме таблеток, капсул или саше.3.
