The short answer
Benefit does not appear immediately. Pooled trial data found no significant difference from control at 4 weeks, with improvement in erectile function scores at 12 and 24 weeks. Beyond 24 weeks the published follow-up is limited.
The Measured Timeline
A 2025 systematic review pooling seven randomized controlled trials across 660 patients measured erectile function scores at set intervals. The pattern was consistent:
| Timepoint | Result vs control |
|---|
| 4 weeks | No significant difference |
| 12 weeks | Significant improvement |
| 24 weeks | Significant improvement |
Two things follow from this. First, if you feel nothing at four weeks, that is expected — the trials found no measurable difference at that point either. Second, benefit appears to build rather than fade over the first six months.
What Happens After 24 Weeks
Honestly: the published evidence thins considerably. Most trials did not follow patients much beyond six months, so statements about duration past that point are extrapolation rather than measurement.
Clinics commonly quote 12 to 18 months. That figure is not well supported by the trial data — it is a reasonable clinical impression, but you should know the distinction.
Building, not fading
Most treatments decline from a peak. PRP appears to do the opposite over the first six months — nothing measurable at 4 weeks, significant benefit at 12, sustained at 24.
That inverted curve is why judging the result early misleads, and why re-treating at six weeks intervenes before you know anything.
What Affects Your Result
- Severity of dysfunction. Men with mild to moderate ED tend to respond better than those with severe disease.
- Underlying cause. Advanced vascular disease, poorly controlled diabetes or nerve damage limit what any regenerative approach achieves.
- Whether the cause is being managed. PRP will not overcome an ongoing medication effect or untreated vascular risk.
- Preparation quality. See above.
Repeat Treatment
Because benefit appears to build to around 24 weeks and evidence beyond that is limited, repeat treatment is usually considered on the basis of how you are doing rather than a fixed schedule. See how many P-Shots you can have.
If you are weighing the ongoing cost against the evidence, our honest assessment is the page to read.
