Senolytics are compounds — ranging from pharmaceutical drugs to dietary supplements — that selectively kill senescent cells (also called "zombie cells"). These cells have stopped dividing but refuse to die, and they secrete a toxic cocktail of inflammatory molecules called the Senescence-Associated Secretory Phenotype (SASP). By age 70, senescent cells can account for 15–20% of the cells in some tissues, driving inflammation, organ dysfunction, and disease.
The strongest evidence base exists for Dasatinib + Quercetin (D+Q), which has human trial data from the Mayo Clinic, University of Minnesota, and University of Texas. Fisetin has strong preclinical data and at least one human Phase 2 trial ongoing (NCT02555878). Natural senolytics like fisetin and quercetin are suitable for self-directed protocols; dasatinib requires physician oversight.
How quickly do senolytics work?
Animal data suggests senescent cell burden decreases within days to weeks of treatment. Human biomarker studies using p16 expression and circulating SASP factors show measurable changes within 3–6 months of periodic dosing.
Can you combine different senolytics?
Yes. Fisetin and quercetin target overlapping but distinct pathways. The dasatinib + quercetin combination is specifically designed to target two complementary survival mechanisms (src kinase and BCL-2). Spermidine complements both via the autophagy pathway.
When should you start senolytics?
Senescent cell accumulation accelerates from age 40 onwards. Most practitioners suggest beginning with natural senolytics (fisetin, quercetin) in your 40s, with pharmaceutical options (dasatinib) considered under physician supervision from your 50s.