What are the possible side effects of APAP/codeine/guaifenesin/phenylephrine?
Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat. Stop using this medication and call your doctor at once if you have a serious side effect such as: fast, pounding, or uneven heartbeat slow heart rate, weak pulse, fainting, weak or shallow breathing confusion, hallucinations severe dizziness, anxiety, restless feeling, or nervousness increased blood pressure (severe headache, blurred vision, trouble concentrating, chest pain, numbness, seizure); or nausea, stomach pain, low fever, loss of appetite, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes) Less serious side effects may include: dizziness, headache constipation mild nausea, vomiting, or stomach upset mild loss of appetite skin rash or itching warmth, tingling, or redness under your skin feeling excited or restless; or sleep problems (insomnia) This is not a complete list of side effects and others
