Nurosym at 3 months: autonomic metrics holding, symptoms still flat
Three months of daily taVNS. HRV is up roughly 35% from baseline and resting heart rate is down 5 bpm, but day-to-day symptoms haven't shifted. This post covers the full dataset, the June regression, and what I think it means.
Three months ago I started daily transcutaneous vagal nerve stimulation with a Nurosym device. The week 3 update reported a promising early picture: HRV up 23%, resting heart rate dropping, but symptoms unchanged. This post covers the full 3-month dataset, what’s held up, what hasn’t, and what I think the data actually says.
The headline numbers
Across the three months since starting the Nurosym (late March to late June 2026), my HRV has averaged around 20ms. That’s up from a baseline of roughly 15ms in the five months before I started the device. My resting heart rate has settled at around 78–79 bpm, down from 83 at baseline.
Those improvements appeared within the first 2–3 weeks, as described in the week 3 post, and have been sustained. The question was whether the early gains would hold or fade. Through May, they held.
In June, there are signs of a modest pullback. My HRV average for the month so far is 19.2ms (down from 20.9 in April and 20.7 in May), and my resting heart rate has crept back up into the low 80s in the last week of the month after spending most of the spring at 77–79.
Symptoms: still flat
My daily fatigue/breathlessness score has hovered at 7 out of 10 for the entire three months. Head pain has been a steady 3. Neither metric has shown any sustained improvement during the period of better autonomic numbers.
In the last two weeks of June, fatigue has actually been slightly worse, averaging closer to 8, with several days hitting 9. This coincides with the slight HRV regression, and has overlapped with extensive periods of very hot weather in the UK.
Summary of period averages:
| Period | HRV average | RHR average | Fatigue avg | Head pain avg |
|---|---|---|---|---|
| Oct–Nov 2025 (baseline) | 14.8 | 83 | 6.3 | 2.5 |
| Feb 2026 (pre-Nurosym) | 15.5 | 81 | 7.0 | 3.2 |
| April 2026 (month 1) | 20.9 | 78.5 | 7.0 | 3.2 |
| May 2026 (month 2) | 20.7 | 78.2 | 7.1 | 3.2 |
| Jun 1–24 (month 3) | 19.2 | 79.0 | 7.9 | 3.5 |
Previous posts: Starting Nurosym: why I’m trying vagal nerve stimulation · Week 3: early HRV gains
The Nurosym device was purchased at my own expense. I have no affiliation with the manufacturer.