Incurin (oestriol 1mg)

Incurin general information

What is Incurin used for?

Incurin tablets 1mg are used to treat hormone-responsive urinary incontinence in female dogs that have had a hysterectomy and had their ovaries removed (spayed or ovariohysterectomised).  Involuntary leakage of urine from the bladder is a common problem for female dogs that have been ovariohysterectomised and is due to a decrease in endogenous oestrogen production (naturally produced by the ovaries).  The urethral sphincter, the muscle controlling emptying of the bladder, can lose muscle tone after ovariohysterectomy which causes the sphincter to become incompetent and allow urine to leak out of the bladder.  Incurin tablets 1mg help prevent urinary incontinence due to sphincter mechanism incompetence. 

How does Incurin work?

Incurin tablets 1mg contains oestriol, a short-acting natural oestrogen which binds to the oestrogen receptor and stimulates oestrogen sensitive responses.  Control of muscle tone of the urethral sphincter is thought to be regulated by oestrogen, which becomes depleted after the ovaries are removed.  Oestriol in Incurin tablets 1mg binds to oestrogen receptors in the smooth muscle cells of the urethral sphincter and stimulates oestrogen-dependent muscle contraction.  This action of Oestriol in Incurin tablets 1mg replaces the action of endogenous oestogen and restores muscle tone to the urethral sphincter and prevents leakage of urine out of the bladder.  Due to the short period of time that oestriol binds to it’s receptor, compared with oestradiol, the endogenous form of oestrogen, reduces the risk of bone marrow depletion seen with oestradiol¹. 

What does Incurin contain?

Incurin tablets 1mg contains the active ingredient oestriol, a short-acting natural oestrogen used to treat hormone-responsive urinary incontinence in ovariohysterectomised female dogs.

Treating urinary incontinence in female dogs with Incurin

Incurin tablets 1mg contains oestriol, a short-acting natural oestrogen that is used to treat hormone-responsive urinary incontinence in female dogs that have had a hysterectomy and had their ovaries removed (spayed or ovariohysterectomised).  Depletion of endogenous oestrogen (naturally produced by the ovaries) is associated with loss of muscle tone in the urethral sphincter, the muscle controlling emptying of the bladder, which allows urine to leak out of the bladder.  Oestriol in Incurin tablets 1mg binds to oestrogen receptors in the smooth muscle cells of the urethral sphincter and stimulates oestrogen-dependent muscle contraction.  This action of Oestriol in Incurin tablets 1mg replaces the action of endogenous oestogen and restores muscle tone to the urethral sphincter and prevents leakage of urine out of the bladder. 

What are the side effects of Incurin?

The most commonly reported side effects when taking Incurin tablets 1mg include: mild, oestrogenic effects such as swollen vulva, swollen teats and/or attractiveness to males only at the higher dose (2mg) and are reversible after lowering the dose.  Other side effects include nausea and vomiting.

When should Incurin not be used?

You should not give Incurin tablets 1mg to your dog if your dog:

• is allergic to oestriol or any ingredients in Incurin
• is pregnant or are breastfeeding
• is younger than one year old
• has polydipsia (increased thirst and water intake) with polyuria (excess urine production) as this indicates a possible medical condition
• is intact and has not been spayed, as Incurin has not been found effective in intact dogs and the incontinence may be due to a medical condition

How should Incurin be given to your dog?

You should give your dog Incurin tablets 1mg by oral administration once daily.  There is no apparent relationship between dose given and the dog’s size or body weight, therefore, it is recommended that the lowest effective dose is given.  You may need to continue to give Incurin tablets 1mg to your dog for the remainder of the life of the dog and you should have your dog re-examined every 6 months during treatment.  If treatment with Incurin tablets 1mg is not effective you should take your dog to a vet to be re-examined as the incontinence may be due to another cause.

Use the following dosage schedule:

The starting dose is one tablet of 1mg Incurin for 7-14 days. 

• If this dose is effective then reduce to half a tablet (0.5mg) for 7 days and then half a tablet on alternate days.  If incontinence returns increase back to 1 tablet of 1mg Incurin.

Or

• If this dose is not effective, increase to 2 tablets of 1mg Incurin for 7 days.  If this is effective reduce to 2 tablets on alternate days.  If the reduced dose is ineffective increase back to 2 tablets per day.

How long should you give Incurin?

You may need to continue to give Incurin tablets 1mg to your dog for the remainder of the life of the dog and you should have your dog re-examined every 6 months during treatment.

Missed dose of Incurin

If you miss a dose of Incurin tablets 1mg give it as soon as you remember, unless it is time to take the next dose, then skip the missed dose.  Do not give a double dose.

How should Incurin be stored?

You should store your Incurin tablets 1mg below 30°C in a cool dry place. 

References

1. Janszen BPM, van Lear PH, Bergman JGH.  Treatment of urinary incontinence in the bitch: A pilot field study with incurin®.  Veterinary Quarterly 1997: 19; sup1, 42-42.