The problem with the monistat and polysporine is that they stay IN the ear and can trap moisture. Now I've used a zillion tubes of monistat in my time with dogs, but you may want to try the Blue Power Ear stuff (along with some of my cautions). SOME dogs can be overly sensitive to one of the anti-bacterials in polysporin ointment. Not all -- but some can. You'll hear a lot of people tell you not to use it for that reason.
Most of the ear stuff the vet gives you has DMSO in it -- which helps the antibiotic cross from the outer ear deeper in (particularly if there is swelling) ... and which also then can cross into the liver and kidneys. ANY TIME you give meds of any sort (and I'm going to include things like flea preps and heartworm preventives as well as ANY antibiotics -- whether topical or oral) it's a darned good idea to give milk thistle to protect the liver and kidneys for at least a few weeks even after you stop the antibiotics (i.e., during and continue after).
The regular "blue" ear cleaner (Chlorhexaderm, etc.) not only can cross into the liver, but even more it will cross the ear drum barrier if there is any sort of rupture (not uncommon in bad ears) and it can deafen them.
But ear infections come in two types. The typical "yeast" ear infection is from moisture in the ears and it particularly troubles flop-eared dogs (cockers to beagles and labs and beyond). BUT I stress here, if you follow these instructions CAREFULLY and thoroughly - doing it every day as directed and giving it the "massage time" it requires, you can kill many ear infections. BUT if the two weeks doesn't totally 'cure' this or if even after a week you see no real improvement GO TO THE VET. I know you've already been there, but I'm saying that for the lurkers reading.
Bacterial ear infections are the other type and they are VERY serious. Not only can they rob a dog of their hearing they CAN KILL if left go. It can cause an abscess in the ear (just like in a tooth only worse) and if that ruptures it will drive infection into the brain and not only is it excruciating IT WILL KILL. Infection in the brain is meningitis and beyond and the dog can die instantly if it ruptures.
Ok, so now everbuddy reading this knows this can be serious. But if you just plain *know* your dog runs recurrent yeasty ear infections, this can help control them.
IF the Blue Power Ear Stuff doesn't totally get rid of this, then you'll have to go to the next level and have the vet do a "culture and sensitivity" test on those ears. Because if there is a bacterial infection deep within, you won't get the ears to heal otherwise.
The Blue Power Ear Solution was first circulated on the AOL Cocker Spaniel Board. This is a home-made recipe and if all you are dealing with is yeast ear infections it will really help them. I gave it to my vets and they refer it all the time. It's actually safer than the purply/blue stuff that the vet sells you (chlorhexiderm can cause deafness if used too much) and it's way cheaper because once you have this you can keep making new batches of it. I often take bottles to folks I know do rescue.
DOWNSIDE - this stuff stains. You ***Must*** put it in their ears outside so they can shake and not stain everything because gentian violet is just like ink!!! However, after you use it, plain alcohol
WILL remove it -- so I've discovered you can even use it on light colored dogs if you're willing to wipe out/off the ears after. But use this stuff outside or where it won't matter.
16 oz. bottle isoprophyl alcohol (just a cheap under a dollarl a bottle)
4 tablespoons boric acid (use human boric acid -- it's about $3.50 at a 'real' pharmacy)
15-17 drops gentian violet (1 or 2% , but the 1% is MUCH cheaper and is fine) - again regular pharmcy
You'll need a medicine dropper to use to measure the gentian violet
Add the boric acid and gentian violet to the alcohol (Yep, it will all fit in that brand new bottle of alcohol -- surprising but true). Shake well.
Transfer some into a squirt bottle (an old shampoo bottle or a hair dye bottle -- anything with a squirt top on it). The boric acid never dissolves til it hits the skin so you have to shake constantly.
The boric acid soothes. The gentian violet deals with the yeast. Even 15 drops of this in a whole bottle of alcohol *does* stain. But it sure works.
Gentian violet is the stuff that they give human babies with "thrush" (oral yeast infection).
The alcohol is the antibacterial - if the ear is really inflamed it can sting **very** briefly -- but this stuff is amazingly soothing and it will calm the itch almost immediately.
If the ear is bad use this twice a day for 2 weeks -- just squirt in and massage behind the ear. The first day don't worry about massaging, but thereafter massage for a minute EACH EAR.
Yes, I'm serious -- COUNT. They'll discover this does NOT hurt, but rather it soothes, and after you are done massaging, they will shake their head violently and all sorts of yuck and junk will fling out. THAT IS GOOD.
After 2 weeks of twice a day, then do a week at least of once a day, then just put it on maintenance once a week.