A New Antibiotic

D. E. Larsen, DVM

New drugs were often exciting, and some of them allowed veterinarians to change the way they treated a group of diseases.

One problem in cattle practice was getting drugs into an animal in an adequate dose and for a sufficient period of time. We had a penicillin that would give us two days of therapy with one injection. Still, we often needed a longer duration of action.

I was always somewhat cautious in using new drugs. I liked to see others use the medicine for a time before I jumped on the band wagon.

“This is an antibiotic that will cure pneumonia with one dose, in many cases,” Fred said as he handed me a new bottle of Micotil 300.

Fred was one of my favorite drug salesmen, and he visited the clinic regularly. He always stopped by once a month and sometimes twice. He lived in Albany, and we were near the end of his day, so his visits were usually in the late afternoon.

“I know, you don’t really want to use it until it is on the market for a time,” Fred said. “This stuff is new, and all these new drugs are a little expensive, but I wanted to show it to you. It will change the way you treat pneumonia in the cow.”

I took the display bottle from Fred and started reading the label as he continued his spiel.

“With one injection, you get blood levels that last for three days at a high level before they start to fall,” Fred continued. “The levels are still at a therapeutic level at five days. So when you factor in labor saved by not handling the animal once or twice a day for injections, it isn’t so expensive. And that doesn’t even consider the stress on the critter from being run through the chute.”

“Fred, I am reading the label, and there looks like there is a major warning here,” I said as I pointed out the boxed warning on the label.

“Well, that is probably a significant warning,” Fred said. “But you are such a fastidious doctor that it probably isn’t anything you have to worry about.”

“It says that accidental injection into a person can be fatal,” I said. “I would call that a little more than significant. I am an old farm boy, you know, and I don’t think there is a cow alive that I consider being worth my life.”

“I knew you would be worried about that,” Fred said. “I have a few bottles that I can give away. I will have them send you one. You can just put it in your truck, and you will have a time to use it sooner or later.”

I never responded to Fred’s comment, I would guess he had a card on me, and he had me pegged pretty well most of the time. He always has some product that he figured I would try. But this drug was probably not one of those.

Several weeks later, Sandy was checking in the supply shipment, and she came to this bottle that was not on the invoice.

“I don’t know what this is,” she said as she showed me the bottle. “It is not listed on the invoice. Do you think it is a mistake?”

I looked at the bottle, and it was that free bottle of Micotil that Fred had said he would have them send to me.

“It’s a new antibiotic,” I said. “Fred said he would send me a free bottle. That is about seventy dollars, our cost, for that bottle. And if you inject yourself by accident, it will possibly kill you.”

Sandy carefully set it on the counter.

“What do you want me to do with it?” Sandy asked.

“I’ll take it and put it in my truck,” I said. “It can outdate there, probably safer than in here. If it got knocked off the shelf and broke on the floor, someone might get an exposure.”

Sandy pushed the bottle back against the wall.

It was probably a year later when Ted called with a sick bull.

“Doc, I have little Brahma bull that is pretty sick,” Ted said. “My problem is he is wild as hell. I have had him for several months, and he still charges me every chance he gets. I don’t know if I can get him in the chute or not.”

“I can get out at the very end of the day,” I said. “Give me a call if you can’t get him caught.”

“That will give time to catch him,” Ted said. “I should be able to get him into the corral, and if I get him in early, I will just put him in the crowding alley and let him stand there.”

I pulled up to Ted’s barn at almost about five-thirty. I could see the young reddish Brahma in the crowding alley. Ted was waiting at the chute, and he looked tired.

“I hope you give this guy a big shot, Doc, because I can almost guarantee you that I am not going to be able to get him back into this chute,” Ted said.

“You need to move your water trough into the corral,” I said. “That way, he will get used to coming in there, and that will make him a little easier to catch.”

“I’ll tell you what,” Ted said. “If you get him back to well, I am going to send him to the sale. I am too old to deal with this guy. He is not only wild, but he is mean. And he isn’t even a year old yet.”

The little bull was fighting us through the rales of the crowding alley. When he finally got to the chute, he was running full speed. Ted slammed the headgate closed and made a perfect catch. The little bull bucked and bawled.

I did somewhat of an exam, but it was difficult. The little bull bucked and kicked every time I touched him. He did have an elevated temperature, and his lung sounds were harsh. I couldn’t listen much because of his behavior.

“What do you think, Doc?” Ted asked.

“I think he has pneumonia,” I said. “I will give him an injection and leave you some more antibiotics to give him twice a day.”

I didn’t crack a smile as I waited for Ted’s response.

“If that is what it is going to take, just hold on, and I will get my rifle and shoot him right now,” Ted said.

“I was just joking, Ted,” I said. “I happen to have a new antibiotic in the truck that will probably do the trick with one dose.”

“That would be great,” Ted said.

“It is a little expensive,” I said. “But it will save you a lot of heartaches.”

I went to the truck, and it took me a little time to find the bottle of Micotil. I carefully drew up a dose for the bull. I gave him a dose at the high end of the treatment range. This one shot was all he was going to get. I read the warning before returning the bottle to its place.

“Ted, if you’re going to sell this guy when he’s well, I’ll make you a deal,” I said. “The drug company gave me this bottle about six months ago, and I haven’t used it because it is a dangerous drug for people. I have never seen a warning on an antibiotic that says it can kill a person if it is accidentally injected. It is supposed to work well in cattle, and one dose should be all his guy needs. I won’t charge you anything for this drug if you promise that I won’t have to see him again.”

“You have a deal, Doc,” Ted said. “I don’t think those ears do any good in this part of the country anyway. And if this guy is an example of their behavior, I think I’m done the breed.”

I reached through the sidebars of the chute to slap the young bull at the injection site behind his left elbow. He exploded as soon as I touched him, bucking and bouncing in the chute so hard that the chute rocked.

“This might be a fun injection,” I said. “I think we want to squeeze him as tight as possible.”

Ted leaned on the squeeze handle, and I stuck the steer with the needle. He exploded again, but I was able to complete the injection. When I pulled the needle out, he jumped again, and that is when it happened. I ended up with a scratch from the needle on my left forearm.

I looked at the scratch and swore, “Damn,” I said. “I knew I should have thrown out that damn bottle long ago.”

“Are you okay?” Ted asked.

“I think so. This is not much of an exposure,” I said. “But if you see me keel over, you might want to get excited.”

I walked over to the truck and poured a bucket of warm water, and scrubbed the scratch vigorously.

“Ted, I will give you a call in a couple of days,” I said. “This guy should be much improved by then. You can’t sell him for meat for thirty days, but as long as the buyer is aware of the withdrawal time, he should be good to go by the end of the week.”

“I would guess that there are plenty of people who would want him for a bull,” Ted said. “That was my thought at first. But I would guess he would pass his attitude along to all his offspring.”

“Behavior is inherited. In cattle, dogs, and people also,” I said.

“What are you going to do with the rest of that bottle?” Ted asked.

“It is going in the trash as soon as I get back to the clinic,” I said. “I told the salesman that a cow wasn’t worth a person’s life when he peddled it to me. My opinion hasn’t changed.”

“I would take it if you are going to just throw it away,” Ted said.

“Nothing personal, Ted, but the stuff isn’t safe for me, and it isn’t safe for you,” I said. “How do you think I would feel if you were injured by this stuff or died. No, it is going in the trash. Others can use it if they want, but not from my clinic.”

When I got to the clinic, I retrieved the bottle from the truck. I removed the cap with a de-capper that Fred had sold me, and I dumped out the contents into some paper towels in the trash and threw the bottle into the trash also.

“What was that all about?” Sandy asked.

“It’s that stuff Fred sent me some months ago. It is a dangerous drug, but I thought it would be perfect for Ted’s ornery bull,” I said. “I injected the bull and preceded to scratch my arm with the needle. That is the last time the stuff will see the inside of this clinic.”


In their warning to veterinarians, livestock owners, and health care providers, they reaffirmed that Micotil is dangerous and has no antidote.
In 2017 the FDA summarized that Micotil 300 had killed at least twenty-five people and hurt thousands over the years of its use. At least sixteen of the twenty-five deaths are suspected of having been suicides.


Photo by Helena Lopes from Pexels.

Published by d.e.larsen.dvm

Country vet for over 40 years in Sweet Home Oregon. I graduated from Colorado State University in 1975. I practiced in Enumclaw Washington for a year and a half before moving to Sweet Home to start a practice.

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