Manipulation of environmental parameters is the best, first choice when attempting to treat early onset and mild RI's in boids. Keep temps in the low 90's 24/7 and humidity at least 70 to 75% for tropical boas and pythons. In some cases, antibiotic use can be avoided if the condition is caught in the early stages. In the very initial stages of an RI, or the similar symptoms of lung irritation caused by low humidity, the condition can many times be reversed by simply raising the humidity. The problem is that this turns into more of an issue when you start raising temps to assist RI treatment, especially with low room humidity in the winter. Warm cage interiors rapidly drive humidity out into the low humidity room, and can quickly lower humidity levels within the cage. For this reason, ambient humidity levels need to be watched even more closely during the winter months. I firmly believe that sub-optimal humidity levels cause as many respiratory issues with tropical boas and pythons as does sub-optimal temps.
Bloods are very sensitive to low humidity levels, but anacondas are more tolerant of low humidity than bloods. It is also very rare to see an anaconda with an RI so you will need to re-evaluate your cage set up for humidity and temp control. General cage temps for both of these species should be in the mid-80’s with a slightly warmer hotspot. How are you currently heating these cages? Also remember that with bloods, it is also very easy to cause respiratory distress with cage temps in the upper 80’s to low 90’s with an ambient humidity that is below 50%.
If the above course of action fails to show any improvement at all within a week, you need to consider a vet visit. This is especially true if you ever see any cloudy or opaque material coughed up by either of these snakes. That indicates a type II RI and would require an immediate vet visit. Good luck.
Kelly