Is it true that doses of klonopin (clonazepam) above 2mg can induce depression by suppressing serotonin?

Depressants: CNS depressants of this type have listed depression as one of the side effects; regardless of dosing. Rebound anxiety, tolerance and feeling of lack of air / shortness of breath are very common collateral effects of benzodiazepines. Pulmonary and allergy tests (like you mention) would be normal in such situation. Ask your dr. Good luck.

Klonopin (clonazepam): Although klonopin's main action is on gaba-a receptors leading to inhibition of neuronal impulses, it also affects serotonin. It decreases 5ht utilization in the brain as well as egress of 5-hiaa from the brain. http://tinyurl.com/muqaacu it apparently upregulates serotonin transporters which do the opposite of ssri's -- take serotonin out of the synapse. Voila -- more depression.