Atenolol/chlortalidone is a combination medicine used in the treatment of hypertension or high blood pressure. The medicine is composed of two active ingredients - atenolol and chlortalidone - each of which works by different means.
For example, Atenolol belongs to the beta-blocker class of drugs - a drug which blocks the beta receptors located on heart tissue. This reduces the workload on the heart. In contrast, chlortalidone is a diuretic, meaning it helps the body eliminate water and salt from the body. This, in turn, reduces the load that the body has to pump around the body.
Common side effects with atenolol/chlortalidone include fatigue, slow heartbeats, depression, nausea, and dizziness.