The adverse effects observed for this combination are essentially the same as those seen with the individual components. Atenolol: Bradycardia, Cold Extremities, Postural Hypotension, Leg Pain, Dizziness, Vertigo, Light Headedness, Tiredness, Fatigue, Lethargy, Drowsiness, Depression, Dreaming, Diarrhea, Nausea, Wheeziness, Dyspnea, Chlorthalidone Orthostatic hypotension, anorexia, gastric irritation, vomiting, cramping, constipation, vertigo, purpura, photosensitivity, rash, urticaria, hyperglycemia, glycosuria, hyperuricemia, muscle spasm, weakness, restlessness.