Phenylephrine HCl may cause muscle shaking (tremor), restlessness, feeling of uneasiness (anxiety), insomnia/sleeplessness, nervousness, dizziness, increased blood pressure, palpitation, irregular heartbeat (arrhythmia), weakness, noisy and congested breathing (respiratory distress), and pallor.
Chlorphenamine Maleate may cause sleepiness and drowsiness. Other undesirable effects include muscle weakness, gastrointestinal discomfort, nausea, vomiting, diarrhea or constipation, dryness of the mouth, nose, and throat, difficulty urinating, ringing in the ears, visual disturbance, blurred vision, insomnia/sleeplessness, tremor, nervousness, irritability, chest tightness, increased or decreased blood pressure, and headache.
Paracetamol, when taken within the recommended dose and duration of treatment, has low incidence of side effects. Skin rashes, hypersensitivity reactions, changes in the number of white blood cells and platelets, and minor stomach and intestinal disturbances have been reported.
Undesirable effects from the use of Ibuprofen are rare, but they may occur: Abdominal pain, nausea, vomiting, heartburn, diarrhea, constipation, indigestion, decreased appetite, flatulence, bloating, stomach ulceration and/or bleeding, gastritis, vomiting with blood, passing black or bloody stools, mouth ulcers, worsening of colitis and Crohn's disease, pancreatitis; Swelling of tissues usually in the lower limbs (edema), fluid retention, increased blood pressure, low blood pressure, irregular heartbeat, palpitations, cerebrovascular accident (stroke), heart failure; Dizziness, headache, nervousness, fatigue, drowsiness, general ill feeling, lightheadedness, anxiety, confusion, mental depression, emotional instability, sensation of tingling, pricking, or numbness of the skin (paresthesia), hallucinations, dream abnormalities, and increased pressure inside the skull (pseudotumor cerebri); Skin rashes, blisters, itching, hives, loss of hair, sensitivity to light or the sun, symptoms of serious allergies (e.g., Stevens-Johnson Syndrome, toxic epidermal necrolysis, erythema multiforme); Low white blood cell count (i.e., leucopenia, neutropenia, agranulocytosis, eosinophilia, pancytopenia), low platelet count, anemia, blood does not clot properly, decrease in hemoglobin and hematocrit, bleeding episodes; Frequent urination, blood in the urine (hematuria), increased nitrogen-containing compounds in the blood (azotemia), decreased creatinine clearance, inflammation of the urinary bladder (cystitis), kidney damage, kidney failure; Abnormal liver function tests, jaundice, inflammation of the liver (hepatitis), liver failure; Benign enlargement of the male breasts, low blood sugar, increased acid in blood and body tissues; Ringing in the ears (tinnitus), decreased hearing, blurred and decreased visual sharpness (amblyopia), depressed vision in the visual field (scotoma), changes in color vision, inflammation or infection of the membrane lining the eyelids (conjunctivitis), double vision, inflammation of the optic nerve, cataracts; Syndrome of abdominal pain, fever, chills, nausea and vomiting; whole-body allergic reaction (anaphylaxis), autoimmune disorders (e.g., lupus erythematosus syndrome, Henoch-Schonlein purpura), rapid swelling beneath the skin (angioedema), serum sickness, dry mouth, gingival ulceration, stuffy nose, worsening of asthma, constriction of air passages of the lungs, wheezing or difficulty in breathing.