I have had my boa constrictor for 6.5 years next month. He hasn't had any issues with anything prior to this. He recently developed a nose whistle, which was later diagnosed as an acute respiratory infection. I gave him treatment and he has since started eating (didn't eat throughout winter). He has become more active and is completely healthy apart from a slight whistle that has hung around and a very small amount of saliva. I have given him a couple doses of an antibiotic (about three weeks of treatments 1-2 weeks off then tried three weeks of treatment, etc). He is acting completely fine apart from this RI still hanging on slightly. I have been measuring his temperatures and everything has been fine... any suggestions on what I could do to help this "cold" bugger off?