Ask the Veterinarian/mometamax


Brad Kenney wrote at 2008-10-26 01:55:44
My 13 year old Westie, much beloved with a huge vocabulary (his hearing is VERY important to him) experienced sudden hearing loss after being perscribed Mometamax.  It was devestating.  Your vet was absolutely wrong - the drug information clearly states that it can cause deafness in geriatric dogs.

Another vet tried to perscribe Neomycin, which is another Aminoglycocide antibiotic - this drug also states it can cause temporary deafness, but with no extra warning for geriatric dogs.  

Heartbroken wrote at 2008-11-15 23:20:06
I would NEVER use Mometamax AGAIN! I was prescribed this by a vet for my dogs ears for yeast infection and she is now DEAF! I noticed that she was no longer hearing me when I came into the house even when I stood beside her and screamed at her, she would go right on sleeping. I then started yelling at her when she was right beside me or behind me. She cannot hear anything! I told my husband I had only noticed it since I used the mometamax and so I pulled out the bottle and read on the contraindications that this medicine can cause permanent hearing loss in older dogs. I have a call in to the vet now, but I am desperately afraid it is too late for my Candy. AND on most sites it states to use for 7 days and the vet that gave these to me said to use for 14 days! I think she is permanently deaf since it has been almost a month and a half since we discontinued treatement and she hears absolutely NOTHING that I can tell. It is soooo sad. I would NEVER have given my pet this medicine if I had known there was even a chance this could happen. She had a KEEN sense of hearing before the medication. If her hearing somehow returns I will post it on this site, but I am very fearful that it is too late for her.

Heartbroken wrote at 2008-12-24 13:38:37
I WAS the person writing as "Heartbroken" when my dog, Candy was prescribed mometamax and went totally and completely DEAF! It has now been several months 2-3 and her hearing has came back. It seems to be as "keen" as it ever was. I am SO happy for her, althought I would still NEVER use this medication again!! And I am still upset that the vet did not tell me this could happen, since I would never have used it had I known "deafness" was a possibility. So for those of you who are experiencing the same problem, do not lose hope. It may be that in 2-3 months your pet's hearing may be restored.

jdimet wrote at 2009-03-30 13:28:36
My 11 year old Golden Retriever lost her hearing over a period of two weeks while using Mometamax. She also had dental work done, which can also cause hearing loss, so it took us a bit to figure it out. She has been off the Mometamax for a week and her hearing is slowly returning. The vet did not tell us this could happen and we have an appointment to tell him today.

jlander wrote at 2009-05-28 23:26:47
My 14 year old toy poodle Peaches was prescribed Mometamax for an ear infection.  After only two days I noticed she was not responding to my voice.  I discontinued use and mentioned to my Vet.  Again my Vet was not aware of any issues with hearing loss in older dogs.  It has been 5 days and no responsiveness.  This is very heartbreaking.

Sarah Danbury wrote at 2009-12-01 08:09:52
My dog is 13 and was treated with Mometamax. She was treated for 10 days, and then for another 10 days the next month when the infection returned. After the second treatment, she seems to have gone completely deaf. The infection is gone, but so is her hearing. It has been nearly 6 months, and her hearing hasn't returned.

Micki wrote at 2010-04-10 13:11:54
My dog Sashi is an 11 year old Pekapoo.  I have only given her two treatments of Mometamax and she is now deaf!  I am so upset, because I asked the Vet if there were any side affects from using this medication and she told me no, other than my Sashi drinking more water than usual.  I failed to read the warning that came with an insert in the box.  Why was this warning not ON the box, because I would of seen it!  I usually read the boxes for warnings and when I did not see one I thought it was ok.  I really hope I caught it soon enough.  Her hearing loss was so sudden and I took her to an emergency Vet to get her ears flushed and to double check her era drums.  Eardrum and all seems fine except for the fact that she can't hear.  I really hope this is temporary like some of the other cases.  

Tigger1013 wrote at 2010-04-15 03:06:22
Our 11 year old Cat Tigger just came out of Dental surgery and he also had problems with allergies in his ears and was treated with mometamax during his surgery, he went deaf no more than 12 hours later and got EXTREME vertigo. We were devastated to learn this as well. Tigger is now on 1/4 human dose of human meclazine. Will this get better?

sevinuv9 wrote at 2010-11-30 18:28:26
My 14 year old wheaten terrier was prescribed 10 days of Mometamax for an ear infection. I noticed that she was totally deaf immediately after the treatment. I hope she is lucky, like Candy, and gets her hearing back. It has been about 1 1/2 months, and so far, she's still totally deaf. This is so sad.  

Susanne wrote at 2010-12-12 19:45:11
My 11 year old Minature Pincher had a slight ear infection in one ear. We took him to his regular vet and he prescibed Mometamax.  Even though the ear infection was only in one ear , the vet said to use it in both because that type of infection normally spread to both ears. We used the Mometamax in both ears for seven days.  On about the fourth day I noticed "Bernie" not listening or ignoring me. By the end of the seventh day I knew something was wrong.  When I would shake the treat jar he would not come, and this always got his immediate attention.  Since I realized this on a weekend, I have had two long days of sadness, anger, crying, and pleanty of reading and investigation on the internet.  We are very upset that our faithful, loyal 11 year old watchdog is now deaf.  I know everything has a potential side effect but this medication should be taken off the market or the skilled Vets should certainly bring this to the attention of us...the pet owners before prescribing it to our senior dogs. I pray that our "Bernie" will make a full recovery.  Any ideas how we can get the attention of the manufacturer? How do you get medication taken off the market?  Class action suit? All I really want is his hearing back....."Frustrated in Florida"

CatWomen wrote at 2010-12-20 16:05:30
Middle ear infection or foreign bodies in the middle ear can also cause deafness. Why is it the assumption that it is the medication alone?

gary wrote at 2012-05-05 21:36:56
Our husky was prescribed Mometamax & after just a few day went totally deaf.  As he is also blind from a genetic condition, losing his hearing is devasting.  The Vet said stop the med immediately which I had already done.  He also said it may come back in 10 days - 2 weeks.  Unfortunately, it has been 1 mont now & still no hearing.  Very upset that we were not told about the side effects, etc.  After talking to a few physician friends (ENT, surgeon & internist) I now now that Gentamicin is rarely used any more in people for the same reasons; i.e., loss of hearing.  Another antibiotic apparently has been routinely used on people for a long time now.  

grnpmpkn wrote at 2012-05-21 17:16:07
Stories like these make me even more furious at the veterinarian profession then I have been. And Iíve been treating my dog with the junk.

I have had several DVM friends through the years, at several clinics in GA, including one of the top animal hospitals in the state and was married to a very knowledgeable vet tech, so I have at least some insight into the field.

The profession started in this country, of course at the start of the country, as an honorable field that folks joined because they loved animals, they never intended to get rich or even try. They knew that the field just didnít hold enough money to make that a possibility, having most of the customer base as farmers and such. These doctors were just glad to help and even gladder the farmers didnít try to treat the animals themselves, which had been the case throughout history (and we still have animals so even that it wasnít a complete failure). As time went by and with the advent of regulation (FDA), and ultra powerful lobbying groups (AMA) this whole attitude began changing. Now instead of having the animal totally as the priority of the field, money has corrupted it, as it normally does and ruined it for the average person.

Now in stead of just treating the animal, or explaining how to do it yourself, if you couldnít afford it, the doctors just a apply a guilt trip. Oh and how successful this guilt trip has worked. I have known of folks that have completely bankrupted themselves over their vet bills. Notice I didnít say over their pets, any of us would sell our soul for a family member. Itís the overcharging! The doctors have an incredible racket now. Apply a guilt trip to get the folks in the door , for all this routine stuff. Charge high prices, to get rich in a field that previously had very little money, still doesnít. Apply the guilt trip again to run up the bills. And tell folks they shouldnít even have animals if theyíre not going to follow their rules (and pay their fees). Oh and donít let me forget, make every that even comes close to working, require a prescription, and even bother writing it and giving it to the patients parents, for fear they would get the Rx cheaper somewhere else. They insist on selling it directly to you or they might fax it to your vendor of choice, ITS A SCRIPT, GIVE IT TO THE PATIENT IN WRITING! Itís a preSCRIPTion! Kind of makes you think of a mechanic, I actually have more respect for them because if a mechanic canít fix your car, you normally donít pay much if nothing. If your pet dies (or they kill them) youíre still going pay brother, all of it!

So anyway I finally realized this after taking my dog to the vet, being miss quoted again and over charged again, (by $75) (oh and sold this med that has probably damaged my dogs ears). Itís not the pet owners and the farmers that refuse to take care of the animal and do the right thing for them, ITS THE DOCTORS. They know that if they took the profession back to where it should be, where a doctor just made enough to make a living and charged fair and reasonable rate, most all folks would bring there animals to them. But because of the CROOKED RACKET the animals suffer, and will continue until we start REGULATING THE VETERINARIANS more.

People have had animals from the beginning of time and no veterinarian is ever going to change that, whether we bring them to the crooks or not. I for one am going back to the old days, I will do the very best I can on my own and itís a whole lot easier with the internet now.

The Doctors only have themselves to blame, I hope they all go broke and then weíll start over.

Diana Rogers wrote at 2012-08-10 02:17:14
Don't give up just yet.  

My Yorkie is 14-1/2 years old.  He started rubbing his ear on the carpet and acted like it was itching him.  I took him to our vet Thursday of last week (8-2-12).  The vet said Rippy had a bacterial infection in his ear and he treated it with Mometamax 30g and instructed me to put it in his ears once a day for 7 days.  I put it in his ears on Friday, Saturday, and Sunday.  Noticed on Saturday that Rippy was not responding when I called him.  By Sunday, I noticed that Rippy was totally deaf.  I was devastated!  I got next to Rippy while he was sleeping and beat on a pot with a spoon, blew a whistle, screamed at the top of my lungs, and he did not hear any of it. I Googled Mometamax and saw all of the negative reviews about it. If only I would have seen this first.  I called our vet and he was unaware of it causing deafness.  He instructed me to bring him back in.  He looked in Rippy's ears to make sure his eardrums were still intact, and they were.  He used a saline solution of some sort and flushed out Rippy's ears.  He used a lot of saline!  Well, low and behold, Rippy can hear again.  He can't quite make out the direction of the sound, but at least he can hear again.  I am hoping this will improve with time. Dr. Ohlandt called me this afternoon with some news for me, but I was not here when he called.  I will call Dr. Ohlandt back tomorrow and post what he tells me.  So, with all of this said so far... don't give up.  Maybe a good saline flushing will help your dog get his hearing back.  I, for one, will never, ever use Mometamax again.  Good luck to all of you.


Charleston, SC

Diana Rogers wrote at 2012-08-13 00:18:37


Ok, I heard back from Dr. Ohlandt.  He called the manufacturer of Mometamax and found out that they are indeed aware of the deafness.  It is the gentamicin that is causing this.  Today, Rippy's hearing is much better.  Probably as good as it was before the Mometamax.  He is still rubbing and scratching his ears though.  I started putting vinegar drops (1 part vinegar, 2 parts water) in his ears this morning. I am also rubbing Lanacane cream (anti itch) on the inside flap of his ears.  He seems much better and lots happier. And he can still HEAR!  Yay!

As I said earlier...  DON'T GIVE UP!  There may be hope.  Maybe the saline flushing will help your doggy get their hearing back.



Lisa wrote at 2012-11-13 22:11:18
My 13-year old Westie has also experienced permanent hearing loss after using veterinarian prescribed Mometamax for an ear infection. This happened after only a few days of use back in June 2012.  I spoke with the vet and he said the drug could be the cause and told me to discontinue use - said his hearing should come back, but it hasn't.  I'm also heartbroken and angry- why would a vet who knows about this side effect prescribe this med to an older dog??  There are other medications for an ear infection.  I must tell my Westie he's a 'good boy' about 100 times a day and have always said those will be the last words he'll hear...not the case any more - so, so sad. He's now 14 and other than being deaf, he's in excellent health.  

Angel wrote at 2013-10-20 14:02:41
I unknowingly gave my 13 year old Bearded Collie a double whammy - she had her teeth cleaned and ears cleaned under anesthesia and was also prescribed Mometemax. Why my vet never informed me that all three of these things can cause deafness boils down to the few hundred dollars she made on it. My dog has completely lost her hearing, and I have lost all respect for my vet. I am furious! I do want to say, however, that a few years ago, I decided to train both my dogs with hand signals in addition to voice commands. I did this on a whim, but now i am reaping the benefits. I am still able to communicate with her, since after nine months, her hearing hasn't returned.

Joyce wrote at 2015-01-28 15:24:33
Please report deafness caused by Mometamax to the company. You can do a search for Mometamax and it will give you the company and contact information. If everyone including vets would report it, the company would see deafness is not so "rare". They are then required to report it to the FDA.

fern hoffman wrote at 2015-04-14 08:21:36
My 13 year old doxie terrier mix was prescribed this drug. I repeatedly asked if it could be ototoxic and was told no. I have just spent nearly 20k on my dog fir thyroid and breast cancer. She had the most amazing vocabulary and ws the smartest dog. I have no children and that little dog was my life. Now she can barely hear the loudest noises. She was my best buddy. I am heartbroken!

Ron wrote at 2015-11-11 17:27:55
My 14 year old Jack Russel "Mallory" developed an ear infection that required laser surgery due to busted blood vessels in her ears. After conferring with our veterinarian we elected to do laser surgery to expedite her recovery and limit her discomfort. Prior to the surgery she was prescribed Mometamax. Unfortunately we were not advised of the dangers associated, specifically potential deafness in geriatric dogs.

We noticed that Mallory no longer hears us when we call her or communicate vocally to her within a week of her surgery and we assumed it could be due to the surgery in both ears and the original infection while she was healing. Now it has been app. 8 weeks and she has lost all hearing. Mallory used to be extremely fearful of thunderstorms with an uncanny sense of impending weather. She was so fearful she would move as close to my wife or I as she could, panting nervously until the storm passed, now she has no emotion at all... We are heartbroken. Mallory is an extremely active and agile dog for 14 and is a loved member of our family. It's disheartening as we now have to assure she sees us to bring her back into the house when she's let out. We can't let her out of the fenced yard for fear that she may endanger herself as she is not aware of the surrounding sounds.

We have discussed this with our veterinarian taking her back this week to assure her eardrums are intact and not ruptured (which they were fine). We further wanted to check to see if there could be build up, blockage or inflammation that could be causing the deafness, unfortunately that was not the case. Our veterinarian indicated that they were not aware of any issues with the Mometamax. We indicated that the information we have read ( specifically state it has been associated with deafness or partial hearing loss in some dogs (e.g. geriatric) especially in older dogs permanent hearing losses or deficits were reported. The post market experience lists deafness as the first item of concern based on voluntary post approval drug experience by veterinarians and pet owners/caregivers

The initial NADA 141-177 Freedom of Information Survey indicated in the initial study for approval of the drug that only one ear was evaluated under inclusion criteria and one dog experienced deafness as an adverse effect (but that reactions reverted to normal after cessation of treatment).

We just wished we had been properly warned and advised by our care professional of the risks associated with this medication if we had been we would never had allowed its use!

We are holding out hope that Mallory's hearing will return.

If you have experienced this please communicate it to your veterinarian and report it to the manufacturer. A CLASS ACTION LAWSUIT IS TRULLY WARRANTED!

Mary O wrote at 2016-01-23 09:05:13
1/7/16 Madison had some tan goop on her ear. I told my husband Chris to mention it to the vet tomorrow at her annual check up. 1/8/16 he asked the vet to check her ears. The vet tech took a swab of both ears, Madison jerked her head. Vet looked in her ears and said that both ears looked good, but one was a little pink. He told her that was the ear that Madison moved when the tech was swabing. Madison is 12 years old. She has never had an ear infection. She did not have any hearing issues. She heard perfectly. Most of the time we call her by simply making a psst noise. When my husband was paying the bill the vet intern came out with a box, he said it was for Madison's ears. My husband asked if she had an infection. The intern said not really, this is just to be safe. Intern told him to use 8 drops in each ear, once a day, for 1 week. 1/9/16 we started the Mometamax ear drops as directed. On Friday 1/15 Madison was asleep by the door and didn't hear us come home. We thought she was just sleeping soundly. Saturday she seemed lethargic. Sunday 1/17 she wasn't listening when we called her. We realized that she was completely deaf. She was sitting between my feet and I screamed her name but she didn't respond. I went online and found out that a lot of other animals have gone deaf using Mometamax. I called Merck, they were closed for the weekend, and Monday they will be closed for Martin Luther King Holiday. We read the warning paper in the prescription box. It said to flush her ears out. We went to the pet store and bought Nutri pet ear wash. We flushed out her ears 2 minutes on each ear, gave her 2 - 25mg Benedril and rushed to Emergency vet. She checked Madison. She said this is a known rare side effect. She prescribed Prednisone steroid twice a day for 3 days, then once a day for 3 days, then 1/2 pill for 3 days then 1/2 every other day for the rest of the 4 week period. She recommended that we do not use any more ear wash, just give it time to heal, and it may take a few months. She said they would fax a report to our vet and we should call our vet to follow up. We called out vet on Monday, she said they use Mometamax all the time, and she has only heard of animals going deaf two times. We told her we would call Merck on Tuesday. She said to let her know how Madison is doing on Wednesday. She said she may want to change the course of the medication. 1/19 I called Merck and Spoke to Dr Sylvester, got a case # & gave her permission to talk to my vet. Dr Sylvester said that 80 percent of animals recover. I was very upset to learn that no one is keeping track of the remedies or solutions that worked in the 80 % of animals that recovered fully. 1/20 I spoke to my vets office and they said after speaking to Merck, my vet agreed that Madison should be on the 5 day cycle of Prednisone instead of the 3 day cycle. I also called the FDA and left a message. I read online that people have been reporting deaf animals from Mometamax since 2010. I want to know what is being done to stop this. Maybe vets need training on what animals are at a greater risk for loosing their hearing. I think that someone should be keeping a database of successful treatments to help more animals make a full recovery. 1/21 I called Merck again because I read online that another case in 2011 also said that 80% of animals recover. I wanted to know if this is the stock answer or if more research has been done since 2011 to increase the odds that Madison will hear again. I also wanted to make sure I was not missing out on a critical window of opportunity to expedite Madisons recovery. Dr Sylvester was out today so I spoke to another doctor. I explained that I did not want to wait 6 weeks and then find out that I could have, or should have done something differently. She assured me that we were doing everything right and unfortunately we can only follow the vets instructions and wait. I called the FDA again and left another message.  I strongly encourage anyone affected by Mometamax to contact Merck co 800-224-5318 and get a case documented. Then contact the FDA & fill out Form  No. 0910-0645 Veterinary Adverse drug Reaction / Lack of Effectiveness or Product Defect Report. The form has to be sent in the mail. You can also call the FDA and leave a message 888-463-6332 or you can email them I want everyone in the world to be aware of the devistating effects we experienced from this medication and I would like some assistance on the collected data to give Madison the most successful chance of recovery.  We are praying that she will recover. Thank you

MaxxandMom wrote at 2016-04-01 01:31:12
My 13 year old, 5lb, Chihuahua was diagnosed with a yeast infection in his ear, although common and previously used Mometamax before (4+ yrs). Unfortunately, after several days on the medication this time I noticed that he was not hearing me. I like most, assumed he was having "selective hearing" or was deep sleeping. But no, he is unable to hear, he is deaf, it has been 2 weeks with no improvement. I am sadden, angry and blaming myself for not clearly researching this medication prescribed. Although I am hopeful, but our vet for 13 years simply tells me it is due to his older age, that I should not believe what is on the web and the medication did not cause this. I am heartbroken and devastated for my baby. Please feel free to contact me,

adry wrote at 2016-05-01 05:53:17
Yes, certain ear drops are capable of making a dog deaf, they are known as ototoxic.

Jen wrote at 2016-05-11 02:39:10
Tri-Otic is a generic of Otomax which also has the same ingredients as Mometamax (gentamicin).  My 9 year old Westie was prescribed Tri-Otic for a mild yeast/bacteria infection in her left ear on April 25, 2016.  Within 6 hours, she was deaf.  We went back to the vet on April 27 and got her ears flushed with saline solution.  It has been almost two weeks since the saline flush and her hearing has almost fully recovered.  She's not hearing as much as she used to before Tri-Otic but I feel relieved that she got a lot of her hearing back.  The vet never informed me of these side effects and I should have looked them up before allowing them to administer the drops in her ears.

Since then, I went for a second opinion/check up May 9, 2016 and the new doctor wanted to prescribe me Mometamax!  I seriously cannot believe she wanted to give me those drops when I told them specifically that my dog had lost her hearing from Tri-Otic.  My dog now has a mild yeast infection leftover from everything and I am currently trying to treat that without using ear medication to make her lose her hearing.  I'm reporting this to the FDA so that they are aware of gentamicin causing hearing loss which is not so rare.

Gloria wrote at 2016-06-17 18:48:00
My 14 year old chihuahua mix was prescribed Mometamax and I gave it to her for the full week that the doctor recommended. She is now totally deaf - I feel so bad that I did not detect the problem sooner and discontinue use of the drops.  Thanks to Mary O's response, I did contact Merck.  A case # has been assigned and a report filed with the FDA.  Unfortunately, all they wil tell you is 'sorry' and wait up to 3 months to see if some of the hearing will return.  Merck says 80% of dogs recover some hearing, 20% never do. I asked Merck why they don't issue more obvious warnings so that vets are aware of the risk.  They said it will be up to the FDA to take any action.  Very disappointing response!  

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Dr. Louis N. Gotthelf


Dermatology and ear diseases of dogs and cats


I am the author of "Small Animal Ear Diseases; An Illustrated Guide" published by W.B. Saunders. I have over 25 years of clinical experience with a special interest in dermatologic conditions and ear diseases.

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