Ok, talked my vet last night. The dosages the vet gave me for Zithro were correct. The doses were 10mg per Kg not pound. But, he also mentioned something about a myco treatment protocol that he came across. He was nice enough to send me a copy of it on Facebook, I've copied and pasted it below.
Rat Chronic Respiratory Disease Protocol
Stage 1: Sneezing, coughing, increased lung sounds. No weight loss or no exercise intolerance. Normal activity.
Doxycycline 5mg/kg PO BID 14 days
Azithromycin 5-10mg/kg PO SID 14 days (compounded anhydrous formulation 50mg/ml – 90 day expiry)
Lower respiratory wheezing Theophylline 10-20mg/kg PO SID to TID permanently (compounded 200mg/ml – 180 day expiry)
Rattling/stertor (upper respiratory) No treatment if only clinical sign If in conjunction with other signs, then steam/nebulise with saline only as need.
Stage 1 (relapse): Start doxycycline and azithromycin at home on initial signs, then revisit if more than 3 months for repeat azithromycin (only stable for 90 days). If within 3 months, then call to advise return of signs to be noted on file.
Stage 2: Mild to moderate weight loss and/or activity level in addition to signs stage 1.
Stage 1 medications: Doxycycline 5mg/kg PO BID 14 days Azithromycin 5-10mg/kg PO SID 14 days (compounded anhydrous formulation 50mg/ml – 90 day expiry)
PLUS: Meloxicam 0.2mg/kg PO BID 7days
Lower respiratory wheezing Theophylline 10-20mg/kg PO SID to TID permanently (compounded 200mg/ml – 180 day expiry)
Rattling/stertor (upper respiratory) Steam/nebulise with saline only as need.
Crackles/gurgles Nebulise with hypertonic saline BID 15 minutes 3-7 days. Be aware that may be, or can become, irritant.
Stage 3: Mild to moderate weight loss and/or activity level Mild to moderate exercise intolerance Sneezing, coughing, increased lung sounds
Stage 2 medications:
Doxycycline 5mg/kg PO BID 14 days
Azithromycin 5-10mg/kg PO SID 14 days (compounded anhydrous formulation 50mg/ml – 90 day expiry)
Meloxicam 0.2mg/kg PO BID 7days Consider changing antibiotics if suspicion of secondary infection.
Options: Clavulox (12.5mg/kg PO BID) – stop azithromycin Enrofloxacin 10mg/kg BID PO
Lower respiratory wheezing Theophylline 10-20mg/kg PO SID to TID permanently (compounded 200mg/ml – 180 day expiry)
One puff of ipratropium BID
IF ON ENROFLOXACIN REDUCE THEOPHYLLINE DOSE BY 30% AS FLUOROQUINOLONES WILL REDUCE METABOLISM OF THEOPHYLLINE.
Crackles/gurgles Nebulise with hypertonic saline BID 15 minutes 3-7 days. Be aware that may be, or can become, irritant.
Stage 4: Severe exercise intolerance Sneezing, coughing, increased lung sounds. Marked anorexia, extreme depression.
Hospitalise on all oral drugs of stage 3. Consider nebulizing 3 x hypertonic saline (7% solution 15 minutes) 2x gentamicin 2 x ipratropium (one puff as needed)
Consider changing to doxycycline injectable to reduce oral medication levels.
Consider starting only on nebulisation until more stable.