yes amoxicillin can definitely cause nausea and possibly depression they say its not likely but in my nursing class they have proven it to occasionally happen
Absolutely! It is possible to get depression from amoxicillin even though it isn't likely.
I found some reports of side effects from this website if you're interested:
http://www.ehealthme.com/drug_interactions_side_effects/Citalopram-Hydrobromide-2855168
Hope this helps!