| G | ||
| Gallarnine Triethiodide | Flaxedil | |
| Gamma Globulin IM | Gamastan, Gammar | |
| Ganciclovir Sodium | Cytovene | |
| Gemfibrozil | Lopid | |
| Gentarnicin | Garamycin, Genoptic | |
| Glipizide | Glucotrol | |
| Glyburide | DiaBeta, Glynase, Micronase | |
| Glycopyrrolate | Robinul | |
| Gold Sodium Thiorrialate | Myochrysine | |
| Griseofulvin | Grifulvin V, Grisactin, Fulvicin PG | |
| Guaifenesin (Glycerol Guaiacolate) | Humibid, Robitussin | |
| Guanabenz Acetate | Wytensin | |
| Guanadrel Sulfate | Hylorel | |
| Guanethidine Monosulfate | Ismelin | |
| Guanfacine HCI | Tenex |