A senolytic peptide that clears aged "zombie" cells to support healthy aging — run in short, cycled courses a few times a year.
Written by Michael Carroll — Owner, Director of Research · Reviewed by the Peptide Initiative Research Team · Editorial standards
Subcutaneous
Route
3 recommended
Sites
Cycled — short courses 2–4 times per year, not daily year-round
Frequency
Preparation
Bacteriostatic water for injection
Alcohol swabs
A sterile syringe for mixing
Insulin syringes for dosing
Your FOXO4-DRI vial
Pro tip
Prepare all supplies on a clean surface before you begin. Having everything ready makes the process smoother and more sterile.
Mixing
Wash your hands thoroughly with soap and water. Gather all supplies on a clean, flat surface.
Remove the plastic cap from the peptide vial and wipe the rubber stopper with an alcohol swab. Let it air dry.
Draw the appropriate amount of bacteriostatic water into a sterile syringe.
Insert the needle into the vial at an angle, aiming at the inside wall of the vial. Slowly push the plunger to let the water trickle down the glass wall -- do NOT squirt directly onto the powder.
Once all water is added, gently swirl the vial in a slow circular motion. Never shake the vial, as this can damage the peptide bonds.
Continue swirling until the powder is completely dissolved and the solution is clear. If particles remain, let the vial sit for a few minutes and swirl again.
Label the vial with the date of reconstitution, the peptide name, and the concentration (e.g. 250mcg per 0.1mL).
Example calculation
A 10 mg vial mixed with 2 mL of bacteriostatic water gives 5 mg per mL — that is 5,000 mcg per mL. On an insulin syringe (100 units = 1 mL), every 10 units holds 0.5 mg. So a 1 mg dose = 20 units, and a 2 mg dose = 40 units.
Dose calculation
Pick your dose, then divide by the vial's concentration to find the volume. Example: at 5 mg/mL, a 2 mg dose = 2 ÷ 5 = 0.4 mL = 40 units on an insulin syringe. For the weight-based protocol, multiply your body weight in kg by 0.4 to get your mg dose, then convert to units the same way.
Pro tip
Always add the bacteriostatic water slowly, letting it run down the side of the vial. Never shake the vial -- swirl gently to avoid damaging the peptide.
Location
Site 01
Abdomen
Pinch the skin 2 inches from navel. Avoid the area directly around the belly button. Rotate between left and right sides.
Site 02
Flank / Love Handle
The soft tissue area on the side of the torso, above the hip. Pinch the skin and inject at a 45-degree angle.
Site 03
Outer Thigh
Middle third of the outer thigh. Keep at least 4 inches above the knee and below the hip. Alternate legs each injection.
Rotate between 3 sites to prevent tissue buildup and ensure consistent absorption.
Pro tip
Rotate your injection sites with each dose to prevent lipohypertrophy (buildup of fatty tissue). Keep a simple log of where you last injected.
Step by step
Swab the site with alcohol and let it dry
Pinch a fold of skin and insert the short insulin needle at about 45–90 degrees
Push the plunger slowly and steadily
Release the skin and remove the needle
Rotate sites each dose to avoid soreness
Pro tip
This peptide uses subcutaneous — a small injection into the fat just under the skin, using an insulin syringe.. Inject at a 45-90 degree angle into pinched skin. Aspirate before injecting to ensure you haven't hit a blood vessel.
Timing
Optimal timing
Best time
Morning is most common. Because FOXO4-DRI is cycled in short bursts rather than taken daily, exact time of day matters less than sticking to your every-other-day or 5-on/2-off schedule.
With food?
Food does not matter — it is injected under the skin, not swallowed, so it works the same whether you have eaten or not.
Stacking notes
Run FOXO4-DRI as its own short cycle. Many people pair senolytic cycles with healthy-aging basics like NAD+ precursors, spermidine, or fisetin between cycles, but keep other senolytics out of the same cycle so you can judge how you respond.
Preservation
Before mixing
Keep the freeze-dried powder frozen at about -20°C and shielded from light until use.
After mixing
Once mixed with bacteriostatic water, keep refrigerated at 2–8°C and use within a few weeks.
Shelf life after mixing
Use reconstituted peptide within a few weeks when refrigerated; discard if cloudy or discolored
Signs of degradation
Discard the vial immediately if you notice any of these:
Cloudiness or particles in the solution
Color change
Powder that has clumped or melted from temperature swings
Important
When to stop
Any signs of an allergic reaction (hives, swelling, trouble breathing)
New or unusual pain, lumps, or unexplained symptoms
A new cancer diagnosis or cancer treatment starting
Any reaction at the injection site that worsens
Simply feeling unwell after use
FOXO4-DRI is a cycled senolytic. Stop a cycle if you feel notably unwell and pick it back up when you recover. If you have a medical condition, loop in a knowledgeable healthcare provider.
Clean technique checklist
Wash hands thoroughly with soap and water before handling supplies
Swab vial tops and injection site with alcohol and let dry
Never touch the needle tip or allow it to contact non-sterile surfaces
Use a new syringe and needle for each injection
Dispose of used sharps in a proper sharps container
Store reconstituted peptides according to the storage instructions above
Published research
Baar MP, Brandt RMC, Putavet DA, et al. · 2017
The foundational study. The researchers designed FOXO4-DRI to break the FOXO4–p53 link that keeps senescent cells alive. In mice, it selectively killed senescent cells, neutralized doxorubicin (chemotherapy) toxicity, and restored fitness, fur density, and kidney function in both fast-aging and naturally aged mice.
Huang Y, He Y, Makarcyzk MJ, Lin H. · 2021
In human cartilage cells (chondrocytes) grown and expanded in the lab, 25 micromolar FOXO4-DRI for 5 days cut the share of senescent (aged) cells from over 40% to under 5%, while leaving minimally aged cells unharmed.
Hu et al. · 2025
In blood-vessel lining cells and in mice (5 mg/kg by intraperitoneal injection every 2 days for one month), FOXO4-DRI lowered aging markers (p21, p16, gamma-H2AX), raised BAX and cleaved caspase-3 while lowering BCL-2, restored vessel-cell tube formation and migration, and reduced artery stiffness and inflammation.
Communications Biology (Nature Portfolio) · 2025
In keloid scar cells, FOXO4-DRI triggered death of senescent fibroblasts by pushing phosphorylated p53 (at serine 15) out of the nucleus, supporting a possible role in scar-related research.
Nature Communications · 2025
Using structural biology, researchers showed that both FOXO4 and FOXO4-DRI bind the flexible (disordered) transactivation region of p53 — pinpointing exactly where the peptide acts.