| Iduronidase, antagonists & inhibitors | Not Available | 1 | 1 | Details |
| IgE-directed Antibody Interactions | Not Available | 1 | 2 | Details |
| Ileal bile acid transport inhibitor | Not Available | 2 | 6 | Details |
| Ileal Bile Acid Transporter Inhibitor | Not Available | 3 | 10 | Details |
| Illicit Drugs | Not Available | 7 | 36 | Details |
| Imidazole and Triazole Derivatives | Not Available | 19 | 116 | Details |
| Imidazole Derivatives | Not Available | 17 | 110 | Details |
| Imidazoles | Compounds containing 1,3-diazole, a five membered aromatic ring containing two nitrogen... more | 110 | 496 | Details |
| Imidazolidines | Compounds based on reduced IMIDAZOLINES which contain no double bonds in the ring. | 17 | 102 | Details |
| Imidazoline Derivatives | Not Available | 2 | 13 | Details |
| Imidazoline Receptor Agonists | Not Available | 5 | 36 | Details |
| Imidazolines | Compounds based on reduced IMIDAZOLES containing a single double bond. | 8 | 52 | Details |
| Imidazothiazole Derivatives | Not Available | 1 | 7 | Details |
| Imides | Organic compounds containing two acyl groups bound to NITROGEN. | 31 | 101 | Details |
| Imines | Organic compounds containing a carbon-nitrogen double bond where a NITROGEN atom can be... more | 18 | 45 | Details |
| Imino Acids | Carboxylic acids that contain an imino group (C=NH). | 39 | 142 | Details |
| Imino Pyranoses | Six-carbon pyranose sugars in which the OXYGEN is replaced by a NITROGEN atom. | 8 | 27 | Details |
| Imino Sugars | Sugars in which the OXYGEN is replaced by a NITROGEN atom. This substitution prevents n... more | 12 | 34 | Details |
| Immune Checkpoint Inhibitors | Immune checkpoint inhibitors work by blocking checkpoint proteins from binding with the... more | 67 | 120 | Details |
| Immune Checkpoint Proteins | Immunomodulators that regulate immune system either in stimulatory or inhibitory fashio... more | 1 | 1 | Details |
| Immune Response Modifiers | Agents that modify immune responses to exert their therapeutic effect(s). | 1 | 3 | Details |
| Immune Sera | Serum that contains antibodies. It is obtained from an animal that has been immunized e... more | 5 | 10 | Details |
| Immune Sera and Immunoglobulins | Not Available | 21 | 28 | Details |
| Immune System | The body's defense mechanism against foreign organisms or substances and deviant native... more | 0 | 0 | Details |
| Immunization | Deliberate stimulation of the host's immune response. ACTIVE IMMUNIZATION involves admi... more | 4 | 2 | Details |