| Nisoldipine Action Pathway (New) |  | Drug Action | ATP / Nisoldipine / Calcium / Magnesium cation |
| Nitrazepam Action Pathway |  | Drug Action | Pyridoxal phosphate / Glutamic acid / ATP / Calcium / Magnesium cation / Nitrazepam / Cyclic adenosine monophosphate / gamma-Aminobutyric acid / Pyrophosphoric acid |
| Nitrazepam Drug Metabolism |  | Metabolic | Nitrazepam |
| Nitrendipine Action Pathway |  | Drug Action | ATP / Nitrendipine / Potassium cation / Calcium |
| Nitrendipine Action Pathway (New) |  | Drug Action | ATP / Nitrendipine / Calcium / Magnesium cation |
| Nitric Oxide Signaling Pathway |  | Signaling | Arginine / Citrulline / Sapropterin / Nitric Oxide / Calcium / Mesoheme / Flavin adenine dinucleotide / Flavin mononucleotide |
| Nitroglycerin Action Pathway |  | Drug Action | Nitric Oxide / Nitroglycerin / Mesoheme / Pyrophosphoric acid |
| Nizatidine Action Pathway |  | Drug Action | ATP / Nizatidine / Potassium cation / Zinc / Acetylcholine |
| Nizatidine H2 Anti-Histamine Action Pathway |  | Drug Action | ATP / Nizatidine / Potassium cation / Magnesium cation / Zinc / Cyclic adenosine monophosphate |
| NMDA |  | Physiological | L-Glutamine / Glutamic acid / Calcium / Magnesium cation |
| Nomegestrol Drug Metabolism |  | Metabolic | Nomegestrol |
| Nomifensine Dopamine Reuptake Inhibitor Action Pathway |  | Drug Action | Pyridoxal phosphate / Tyrosine / ATP / Dopamine / Levodopa / Calcium / Magnesium cation / Iron / Cyclic adenosine monophosphate / Nomifensine |
| Non-Ketotic Hyperglycinemia |  | Disease | Pyridoxal phosphate / Tetrahydrofolic acid / Ademetionine / Pyruvic acid / Arginine / Adenosine phosphate / Serine / Methionine / Glutamic acid / Glycine / Creatine / Cysteine / NADH / Alanine / ATP / Aminolevulinic acid / Magnesium cation / Zinc / N,N-dimethylglycine / Glycocyamine / Oxogluric acid / 3-Hydroxypyruvic Acid / Orotidylic acid / Flavin adenine dinucleotide / Pyruvaldehyde / Formaldehyde / 2-Amino-3-Ketobutyric Acid / D-Serine / Pyrophosphoric acid / Glyoxylic acid / Dexfosfoserine / 2-Oxobutanoic Acid |
| Non-Ketotic Hyperglycinemia |  | Disease | Pyridoxal phosphate / Tetrahydrofolic acid / Ademetionine / Pyruvic acid / Arginine / Adenosine phosphate / Serine / Methionine / Glutamic acid / Glycine / Creatine / Cysteine / NADH / Alanine / ATP / Aminolevulinic acid / Magnesium cation / Zinc / N,N-dimethylglycine / Glycocyamine / Oxogluric acid / 3-Hydroxypyruvic Acid / Orotidylic acid / Flavin adenine dinucleotide / Pyruvaldehyde / Formaldehyde / 2-Amino-3-Ketobutyric Acid / D-Serine / Pyrophosphoric acid / Glyoxylic acid / Dexfosfoserine / 2-Oxobutanoic Acid |
| Noncanonical Wnt/Ca2+ signaling |  | Signaling | Calcium / Magnesium cation |
| Norelgestromin Action Pathway |  | Drug Action | NADH / ATP / Progesterone / Testosterone / Estrone / Potassium cation / Calcium / Magnesium cation / Androstenedione / Cyclic adenosine monophosphate / Mesoheme / Pyrophosphoric acid / Cholesterol / Norelgestromin / 2-Hydroxyestradiol |
| Norelgestromin Drug Metabolism |  | Metabolic | Norelgestromin |
| Norepinephrine Alpha 1A Adrenergic Blood Vessel Relaxation Action Pathway |  | Drug Action | ATP / Norepinephrine / Calcium / Magnesium cation |
| Norepinephrine B2-Adrenergic Artery Dilation Action Pathway |  | Drug Action | ATP / Norepinephrine / Potassium cation / Calcium / Magnesium cation / Cyclic adenosine monophosphate |
| Norepinephrine Beta-1 Adrenergic Cardiac Action Pathway |  | Drug Action | ATP / Norepinephrine / Calcium |
| Norepinephrine Neurological |  | Physiological | Pyridoxal phosphate / Ascorbic acid / Tyrosine / Norepinephrine / Dopamine / Levodopa / Calcium / Iron / Pyrroloquinoline Quinone |
| Norethisterone Action Pathway |  | Drug Action | NADH / ATP / Progesterone / Testosterone / Estrone / Norethisterone / Potassium cation / Calcium / Magnesium cation / Androstenedione / Cyclic adenosine monophosphate / Mesoheme / Pyrophosphoric acid / Cholesterol / 2-Hydroxyestradiol |
| Norgestrel Action Pathway |  | Drug Action | NADH / ATP / Progesterone / Testosterone / Estrone / Potassium cation / Calcium / Magnesium cation / Androstenedione / Cyclic adenosine monophosphate / Mesoheme / Pyrophosphoric acid / Cholesterol / 2-Hydroxyestradiol / Norgestrel |
| Norgestrel Predicted Metabolism Pathway |  | Metabolic | Mesoheme / Norgestrel |
| Normethadone Action Pathway |  | Drug Action | ATP / Calcium / Magnesium cation / Cyclic adenosine monophosphate / gamma-Aminobutyric acid / Pyrophosphoric acid / Normethadone |