Listeriosis is a disease caused by infection with a gram-positive, rod-shaped bacterium called Listeria monocytogenes. Listeria monocytogenes is ubiquitous, and it is usually found in soil, water, and decaying vegetation.
Common side effects of Plaquenil include. 1  nausea, 2  vomiting, 3  stomach pain or cramps,  loss of 1  appetite, weight loss, 2  diarrhea, dizziness,  spinning 1  sensation, headache,  ringing in 1  your ears, mood  changes, 1  nervousness, irritability,  skin rash, 1  itching,  or. hair loss.
Plaquenil Overdose. Since a Plaquenil (hydroxychloroquine) overdose can be lethal, it is important to seek medical attention immediately if you think you may have taken too much of the medication. Vision changes, seizures, or cardiac arrest may also occur as a result of taking too much Plaquenil.