Yes, your cool 'end' should not be below 75. if you are seeing strange symptoms--I would increase the ambient of the entire enclosure to 80F (which is not easy in a 40 gallon tank).I've also got another heat dome on the way that has a higher watt capacity than the current one. Hoping using a higher watt bulb will pump in a bit more heat.
As for the allergy to Reptile Prime--I'm not certain if there is an allergy test for snakes currently. Human blood and inflamed tissue usually have increased levels of eosinophil cells--not sure if it is comparative to reptiles....if so, a blood or tissue test against a statistical average should identify it. Otherwise it is just purely a guess.![]()