Suppression of the insulin–IGF–mTORC1–Ras network ameliorates aging in animals. Many drugs have targets in the network because of its roles in cancer and metabolic disease and are candidates for repurposing as geroprotectors. Rapamycin, an established geroprotective drug, blocks mTORC1 signaling, and trametinib inhibits the Ras–MEK–ERK pathway. In this study, we assessed survival and health of male and female mice treated with trametinib, rapamycin or their combination. We show here that trametinib treatment extended lifespan in both sexes and that its combination with rapamycin was additive. Combination treatment reduced liver tumors in both sexes and spleen tumors in male mice, blocked the age-related increase in brain glucose uptake and strongly reduced inflammation in brain, kidney, spleen and muscle and circulating levels of pro-inflammatory cytokines. We conclude that trametinib is a geroprotector in mice and that its combination with rapamycin is more effective than either drug alone, making the combination a candidate for repurposing as a gerotherapy in humans. Gkioni et al. show that trametinib, which targets the Ras–Mek–Erk pathway, extends lifespan in male and female mice and that co-treatment with the known geroprotector rapamycin additively extends lifespan and healthspan, reducing inflammation and tumor growth.