Doxy-minocycline? Anyone have experience?

We took our chronically ill Flemie to the vet this past week. After treating unsuccessfully for an "infection" in his throat which does not seem to be dental related, nor does he have any symptoms of respiratory issues, and he has recently had a dental trimming/inspection. We have a very rabbit savvy vet who has tried to be budget conscious, and has tried to resolve this strange issue for a while. Anyways, getting back to this week, he has been treated with Baytril and was not completely responsive, so the vet recommended Doxycycline, but the medicine that the vet tech gave us is Doxy-minocycline. From what I have read, giving doxycycline and minocycline can cause pleuracy? in rabbits possibly. He is about an 18 pound Flemie, so she is giving him a 100mg dosage through pill form (we will mix with water and possibly banana and deliver orally through one of the med syringes (not the kind with a needle)). I looked up proper dosage for rabbits for Docycycline, and it says according to his weight, he should only be getting 25mg. I'm going to call the vet to make sure that we have the right meds and the right dosage, but wondered if anyone else here has used this and knows about the dosage issue? I just want to be sure since we have never given this before. Anyone who has used it - did you have any stomach issues or other issues?

The dosage for doxycycline pulbished in Quesenberry and Carpenter's Ferrets, Rabbits and Rodents, Clinical Medicine and Surgery is 2.5 mg/kg orally every twelve hours which would be about 20 mg twice a day for an 18 lb rabbit. I have used this dosage safely in my own rabbits although they were on the vibramycin forumaltion of doxy which was also rasberry flavored (which they loved).
Cricket was on doxy for several months (we're currently trying no antibiotics to see if her sneezing gets worse or if she's okay) and Watson was on it for about 2 months. Neither of them had any GI issues.
I'm not familiar with using minocycline in rabbits although it is a tetracycline antibiotic like doxycycline. The only pleural related articles I'm finding are following intrapleural administration of the drug, whereas I believe you're planning to give it orally.

Thanks. I called the vet and she said she can't get any doxycycline because it's too costly and difficult to get. She assured me that this dosage and this med is completely safe for our rabbit. I have to trust her - she is very rabbit savvy and has never steered us wrong. She runs a rabbit rescue as well. We did give this dosage, broke the pill open, mixed with water, and a small amount of banana (because they said it might taste bitter). Our Flemie took it like a champ. Now we will watch him and see how he reacts. I hope this is the med that will help him get over whatever this is. The next step is to do a flush and take a throat culture when he goes for his next dental trimming/check up. If that doesn't present anything, they will do a nasal culture, and if that doesn't help, we will only have one other option - that is to get him scoped, and I read that is very costly. She said it could be something stuck in his throat though because the infection never goes to his lungs and he never has any snot or any real symptoms present besides a snorty sound coming from his throat. So, we are just waiting things out. Thanks for the info!