Nitrofurantoin

But you're saying Bactrim, Bactrim, uh, is not the one.

Macrobid.

Macrobid.

Well, not only that, but the product insert says it requires an acid pH to work.

Well, this population with high ammonia doesn't have an acid pH, so I knew intuitively for decades that in this chronic population the Macrobid wasn't working.

I just didn't, couldn't explain why.

Now I know why.

For women who have chronic UTIs, often it's because the vaginal tract is colonized with bacteria and those keep seeding into the bladder.

And unfortunately, the most commonly prescribed antibiotic for UTI is Macrobid.

Macrobid gets cleared by the urinary tract 90% and will never touch any bad bacteria in a woman's vagina.

So she keeps getting the urinary tract treated, maybe probably appropriately, but because the reservoir of infection is in the vagina and that's never getting treated, she just keeps reinfecting and reinfecting and reinfecting.

We also have the issue that 25% of the sexual partners of women also have an undiagnosed asymptomatic prostatitis.

Nitrofurantoin, however, only has a half-life of 20 to 30 minutes.

If they put the macro crystals in, it now has a half-life of 45 minutes.

So treating with Macrobid twice a day It may work for the occasional acute patient, but rarely, if ever, works for the chronic patient because of the short half-life.

Okay, so the next one is nitrofurantoin.

As everybody knows, it comes in two formulations, and they are not interchangeable.

First one, brand name is Macrobid, which is the monohydrate macrocrystals form.

That one is dosed 100 milligrams twice daily for five days.

It's preferred because that twice daily dosing is easier for patients to stick to versus the next crystal form, which is macrocrystals only, a brand name Macrodantin.