Incurin typically takes about two weeks to show initial improvement, with full results by six weeks. In FDA clinical trials, about 25% of dogs were fully continent after 14 days, and nearly 90% were either continent or significantly improved by day 42. So if your dog just started Incurin, give it at least two weeks before judging whether it’s helping, and up to six weeks before expecting the best results.
What to Expect in the First Two Weeks
Every dog starts on the same dose: 2 mg (two tablets) once daily for a minimum of 14 days. This initial loading period lets the medication build up its effects on the tissues around the urethra. By the end of those two weeks, roughly half of dogs in clinical trials showed some degree of improvement, and about one in four were already fully continent. The other half hadn’t visibly responded yet, which is normal.
During this period, you may not notice any change at all in your dog’s leaking. That doesn’t mean the medication isn’t working. Incurin strengthens the tissues supporting the urethra gradually, increasing muscle tone and improving the seal that keeps urine in the bladder. These tissue-level changes take time to translate into fewer wet spots on the bed.
The Six-Week Mark
The clearest picture of whether Incurin is working comes at around six weeks. In the FDA trial of 118 dogs, 67% had no incontinence at all by day 42, and another 23% were significantly improved. That’s roughly 90% of dogs responding favorably. The remaining 10% showed little or no change.
If your dog is still leaking frequently after six full weeks on the starting dose, it’s worth talking to your vet about whether a different approach is needed. But most dogs fall somewhere on the improvement spectrum well before that point.
How Incurin Works
Incurin contains estriol, a mild form of estrogen. Spayed female dogs lose their natural estrogen supply after surgery, and over time this can weaken the muscles and tissues that hold the urethra closed. The result is “spay incontinence,” where urine leaks out involuntarily, often while the dog is sleeping or relaxed.
Estriol restores some of what was lost. It strengthens the connective tissue around the urethra, improves blood flow to the area, and makes the smooth muscle of the urethra more responsive to the nerve signals that keep it shut. Think of it as restoring tone and elasticity to a muscle that had gone slack. This is a gradual biological process, not an on/off switch, which is why improvement unfolds over weeks rather than days.
Dose Adjustments After Improvement
Once your dog’s incontinence is under control, the goal is to find the lowest dose that still works. Your vet will reduce the dose in steps: from 2 mg daily down to 1 mg daily, then to 0.5 mg daily, with at least seven days between each reduction. If incontinence returns at a lower dose, you go back up one step.
In clinical data, about half of dogs were successfully maintained on less than 2 mg daily, and 99% of those dogs remained improved or fully continent. Some dogs can eventually move to dosing every other day instead of daily. Each step down adds a bit of time to the overall process, so the full journey from starting Incurin to settling on the right long-term dose can take two to three months.
What If It’s Not Working Yet
If you’re at the one-week mark and seeing no change, that’s completely expected. Even at two weeks, more than half of dogs in clinical trials hadn’t reached full continence yet. The trajectory matters more than any single day. Look for small signs of progress: slightly drier bedding, fewer accidents, or smaller wet spots. Partial improvement at two weeks often becomes full continence by six weeks.
If you’re past six weeks with no improvement at all, Incurin may not be the right fit for your dog. Some dogs with urinary incontinence have causes beyond low estrogen, such as structural problems, nerve issues, or urinary tract infections that need separate treatment. Your vet can help distinguish between these possibilities.
Long-Term Use
Incurin is a lifelong medication for most dogs. It manages incontinence rather than curing it, so stopping the tablets typically means the leaking returns. Dogs on long-term treatment should be re-examined every six months to make sure the dose is still appropriate and no new health issues have developed. Most dogs tolerate estriol well over extended periods, particularly once they’ve been titrated down to the minimum effective dose.