My wife is taking prozac (fluoxetine) primarily for ibs relief (been on it 2 weeks). she has a severe cold and i want to know if nyquil would be ok or not.

Caution: Nyquil and many cold/cough OTC meds contain dextromethorphan, a cough suppressant, which can interact with serotonergic antidepressants like Prozac (fluoxetine) to increase risk for serotonin syndrome. Ask pharmacist for advice to avoid dextromethorphan. See: http://www.mayoclinic.org/diseases-conditions/serotonin-syndrome/basics/definition/con-20028946 I hope this helps. Best wishes.