Well, from the time treatments start, it's going to take probably a week or so to really start to see any "real" difference I would think, but it really depends on many things, every situation is different, and every animal is different, this also greatly depends on the severety, which I suspect is pretty substancial as well from it's behavior and gaping. The snake as you could imagine is very uncomfortable.
Also, I have no idea what type, or what dosage your vet recommended you give the snake. Below is a list of some antibiotics that are commonly used for reptiles.
#1 Amikacin, and #5 Baytril are very well known reptile antibiotics, and I have personally used them before with success in the past. Do yourself a favor, and check to see if your vet prescribed one of these for your snake, and see if his dosages match these as well,...THAT way, we'll know if he seems to know what he's doing. Of course there are certainly other drugs that are also used that are NOT on this list too, but if he is using any of these, the dosages your vet recommended should closely match up.
ANTIBIOTICS
1. Amikacin sulfate (Amiglyde-V). Can administer a loading dose of 5 mg/kg IM and then 2.5-3.0 mg/kg every 72 hours for 5 treatments total. Potentially nephrotoxic so animals should be well hydrated.
2. Ceftazidime (Fortaz). This human cephalosporin drug has proved to provide good broad spectrum activity in a variety of reptiles with the advantages that its half life is long and it kills Pseudomonas. Dose is 20 mg/kg IM or SC Q 72 hours
3. Chloramphenicol (Chloromycetin). A bacteriostatic drug administered either IM or IV at a dose of 30-50 mg/kg/day for 7 to 14 days. Good activity against many gram negative bacteria but a potential human health hazard.
4. Clindamycin. A drug that is effective against anaerobic organisms when used at a dose of 5.0 mg/kg PO Q 24 hours.
5. Enrofloxacin (Baytril). A quinolone compound that appears to be safe and effective in reptiles. May be used IM, SQ and PO at a dose of 5-10 mg/kg/day for 7-21 days. May be diluted with sterile saline since the concentrated form (2.27%) may be irritating.
6. Gentamicin sulfate (Gentocin). A potent aminoglycocide which takes care of most gram negative organisms. Has a smaller therapeutic window than amikacin and may be more nephrotoxic. Animals must be well hydrated. Dosed the same as amikacin.
7. Trimethoprim sulfadiazine (Tribrissen). A good broad spectrum antibiotic. Dose is 15-25 mg/kg/day IM for 7-14 days.
Living in south Florida, I don't really need to use much in the way of heaters, and in the winter, I use a space heater for the entire room. But on occasion I have simply used a generic heating pad bought from any drug or department store. Use one that has several settings, and start with the "LOW" setting underneath approx. 1/3 or so of the enclosure. Keep in mind, you MUST do a trial FIRST with this to make sure it doesn't get too hot, remember, it depends on if you have a solid top with only small holes, or screen lid, etc... this is what will dictate how much heat is retained, or lost, so you must ajust accordigly. Jut common sense here really. Just play it safe and set the enclosure with the heating pad on something that's not flammable, or can get too warm. Make some adjustments if you have to, by using different things around the house to add more direct spacing from the mat if need be. Just make sure you monitor temps with a thermometer, and DO NOT GUESS!
best regards, ~Doug
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"Better to be silent and thought a fool, than to open mouth and remove any doubt!"