1. A dosage form containing tetrahydrobiopterin or its metabolic precursor, characterized in that it contains an aqueous solution of tetrahydrobiopterin or its metabolic precursor and an antioxidant in a dilution mixer and a metering device for dispensing an aqueous solution. ! 2. The dosage form according to claim 1, characterized in that the antioxidant is a sulfhydryl compound. ! 3. The dosage form according to claim 2, characterized in that the sulfhydryl compound is a cysteine compound, especially selected from the group of cysteine and its derivatives, in particular selected from the group comprising N-acetylcysteine, homocysteine, N-acetylhomocysteine, methyl complex cysteine ester, cysteine ethyl ester, homocysteine methyl ester or homocysteine ethyl ester； or mixtures of two or more different sulfhydryl compounds, optionally in salt form, especially in the form of hydrochloride. ! 4. The dosage form according to claim 1, characterized in that tetrahydrobiopterin or its metabolic precursor is present in a concentration of from 0.5 wt.% To 50 wt.%, In particular 2-20 wt.%, In particular 5-15 wt. % ! 5. The dosage form according to claim 1, characterized in that the molar ratio of tetrahydrobiopterin or its metabolic precursor to antioxidant comprises a ratio of from 1.5: 1 to 1: 4, in particular from 1: 1 to 1: 1.5. ! 6. The dosage form according to claim 1, characterized in that the pH of the aqueous solution lies below 5, especially below 2.! 7. The dosage form according to claim 1, characterized in that the metering device promotes the release of aliquots of the aqueous race1. Лекарственная форма, содержащая тетрагидробиоптерин или его метаболический предшественник, отличающаяся тем, что она содержит водный раствор тетрагидробиоптерина или его метаболического предшественника и антиоксидант в разводящем смесителе и дозирующее устройство для дозирования водного раствора. ! 2. Лекарственная форма по п.1, отличающаяся тем, что антиоксидант представляет собой
