Adverse reactions which have been reported with the use of antihistamines are as follows:
Central Nervous System: Sedation and sleepiness (often transient), dizziness, disturbed coordination, confusion, restlessness, excitation, nervousness, tremor, irritability, insomnia, paresthesias, neuritis, convulsions, euphoria, hallucination and hysteria, drowsiness.
Dermatologic Effects (Integumentary): Allergic manifestation of skin rash and edema, excessive perspiration, urticaria, photosensitivity.
Special Senses: Acute labyrinthitis, blurred vision, diplopia, vertigo, tinnitus.
Cardiovascular: Hypotension, palpitation, tachycardia and arrhythmias, extrasystoles, anaphylactic shock.
Hematologic: Hemolytic anemia, leukopenia, agranulocytosis, thrombocytopenia.
Digestive System: Cholestasis, hepatic failure, hepatitis, hepatic function abnormality, dryness of mouth, epigastric distress, anorexia, nausea, vomiting, diarrhoea, constipation, jaundice.
Genitourinary: Urinary frequency, difficult urination, urinary retention, early menses.
Respiratory: Dryness of nose and throat, thickening of bronchial secretions, tightness of chest and wheezing, nasal stuffiness.
Miscellaneous: Fatigue, chills, headache, increased appetite/weight gain.