Axonics therapy is a form of sacral neuromodulation, a treatment that uses mild electrical pulses to stimulate the sacral nerve near the base of the spine to improve bladder and bowel control. It’s designed for people with overactive bladder, urinary retention, or bowel incontinence who haven’t found relief through medications or behavioral treatments. The system involves a small implanted device, roughly the size of a large coin, that sends signals to the nerves controlling these functions.
How Sacral Neuromodulation Works
The sacral nerves sit at the lower end of the spinal cord and play a central role in communication between the brain and the bladder, bowel, and pelvic floor muscles. When those signals misfire, the result can be an overactive bladder that constantly feels urgent, a bladder that won’t empty properly, or loss of bowel control.
The Axonics system places a thin wire (called a lead) near the sacral nerve. That lead connects to a small pulse generator implanted in the upper buttock area. The generator delivers gentle electrical pulses to the nerve, essentially recalibrating the faulty signals between the brain and pelvic organs. You don’t feel a jolt or shock. Most people describe the sensation as a light tapping or tingling, and many stop noticing it over time.
Conditions It Treats
The FDA has approved Axonics therapy for three primary conditions:
- Overactive bladder, including urge incontinence (leaking when you feel a sudden, strong need to go) and urgency-frequency (needing to urinate far more often than normal)
- Urinary retention, where the bladder doesn’t empty completely on its own
- Fecal incontinence, or the inability to control bowel movements
It’s specifically intended for people who have already tried more conservative options, such as pelvic floor exercises, bladder training, or medications, without adequate improvement. It is not appropriate for urinary problems caused by physical blockages like an enlarged prostate, tumors, or a narrowed urethra.
The Trial Phase Before Implant
One of the key features of sacral neuromodulation is that you get to test it before committing to a permanent implant. During a trial phase, a doctor places a temporary lead near the sacral nerve and connects it to an external device you wear on your waistband. You go about your daily life for roughly one to two weeks, tracking your symptoms in a bladder or bowel diary.
If your symptoms improve by at least 50% during the trial, you’re considered a good candidate for the permanent implant. If the trial doesn’t help, the temporary lead is simply removed with no lasting effects. This try-before-you-buy approach is a major reason doctors and patients favor sacral neuromodulation over more invasive surgical options.
What the Permanent Implant Looks Like
If the trial succeeds, the permanent procedure involves placing a small pulse generator beneath the skin of the upper buttock. The Axonics system comes in two versions: a rechargeable model (R20) and a non-rechargeable model (F15).
The rechargeable R20 has a volume of about 5 cubic centimeters, making it one of the smaller neurostimulators available. It requires about one hour of wireless charging per month, done through a small external charger held against the skin. Its battery is designed to last over 20 years before needing replacement.
The non-rechargeable F15 is slightly larger at 10 cubic centimeters but requires no charging at all. At standard settings, it’s expected to last 15 or more years, and at lower energy settings, that can extend past 20 years. For people who don’t want to think about maintenance, the F15 offers a set-it-and-forget-it option. For those who prefer a smaller device and don’t mind occasional charging, the R20 is the trade-off.
Both models are MRI conditional, meaning you can still get MRI scans under specific safety guidelines. This is worth noting because older neurostimulator technology often made MRI scans off-limits entirely.
How Effective It Is
Clinical data from the ARTISAN-SNM study, one of the largest trials of the Axonics system, found that 89% of participants were therapy responders at the one-year mark. “Responder” in this context means achieving at least a 50% reduction in urinary urge incontinence episodes compared to baseline. That’s a strong response rate for a condition where medications often produce modest improvements and come with side effects like dry mouth and constipation.
For many patients, the improvement goes well beyond 50%. Some experience a near-complete resolution of leaking episodes. The therapy tends to work consistently over time rather than wearing off, which is one of the advantages over medications that can lose effectiveness or become harder to tolerate.
How It Compares to InterStim
Axonics entered the market as a competitor to Medtronic’s InterStim, which was the only sacral neuromodulation system available for over two decades. The primary differences come down to device size and battery management.
Medtronic’s smallest option, the InterStim Micro, measures 17 by 47 millimeters and needs about 20 minutes of charging per week with a battery life exceeding 15 years. The Axonics rechargeable device is slightly larger at 23 by 45 millimeters but only needs charging once a month. Medtronic also offers the InterStim X, a non-rechargeable model with a 10 to 15 year battery life, which is comparable to the Axonics F15.
Both systems target the same nerve and work on the same principle. The choice between them often comes down to your doctor’s experience with each platform, your preference for charging schedules, and how important device size is to you. Neither system has demonstrated clear clinical superiority over the other in head-to-head comparisons.
What Recovery and Daily Life Look Like
The permanent implant procedure is typically done as an outpatient surgery under light sedation or general anesthesia. Most people go home the same day. Soreness at the implant site is common for a week or two, and doctors generally recommend avoiding heavy lifting, bending, and strenuous activity for several weeks while the lead settles into position.
Once healed, the device runs in the background. You control the stimulation level using a small handheld remote, which lets you adjust intensity or turn the device on and off. Most people find a setting that works and rarely need to make changes. The implant doesn’t restrict most daily activities, including exercise, travel, and bathing. For the rechargeable model, the monthly charging session is straightforward: you hold a wireless charger against the implant site while sitting or lying down.
Over time, if the battery eventually depletes, only the pulse generator needs to be replaced through a minor procedure. The lead wire near the nerve typically stays in place permanently.