Xylitol (1 g)

Xylometazoline Hydrochloride (250 mg)

Xylometazoline Related Compound A (25 mg) (N-(2-Aminoethyl)-2-[4-(tert-butyl)-2,6-dimethylphenyl]acetamide)

Xylose (1 g)

Yohimbine Hydrochloride (200 mg)

Zalcitabine (200 mg)

Zalcitabine Related Compound A (50 mg) (2',3'-Didehydro-2',3'-dideoxycytidine)

Zaleplon CIV (200 mg)

Zaleplon Related Compound A (15 mg) ((E)-N-(3-[3-(dimethylamino)acryloyl]phenyl)-N-ethylacetamide)

Zaleplon Related Compound B (15 mg) (N-[3-(3-Cyanopyrazolo[1,5-alpha]pyrimidin-5-yl)phenyl]-N-ethylacetamide)