BACKGROUND: Is the timing of dosing for amlodipine and atorvastatin important with regard to therapeutic efficacy? To answer this question, we designed an outpatient, practice-based, case-control study lasting 8 weeks.

MATERIAL AND METHODS: Two hundred patients were divided into 2 groups: in Group I, patients were provided with a single pill containing amlodipine/atorvastatin (5/20 mg) to be taken each night at 10 pm, and in Group II, patients were taking amlodipine (5 mg) and atorvastatin (20 mg) each morning at 7 am.

RESULTS: Our results indicated no obvious difference in blood pressure control between the 2 groups. Taking amlodipine at night not only lowered blood pressure, but it also provided better control during the peak blood pressure in the morning. Hypercholesterolemia control in the 2 groups was also not significantly different, taking atorvastatin in the morning was as effective as dosing at night in patients with hypercholesterolemia. While the carotid IMT, hs-CRP, and LVMI were significantly lower after treatment, no differences were found between the 2 groups. Although no obvious difference was found in adverse drug reactions between the 2 groups, compliance was much better in the single-pill group than in patients taking the 2 medications separately.

CONCLUSIONS: In conclusion, single-pill amlodipine-atorvastatin taken at night can lower blood pressure and reduce the morning peak blood pressure levels the next day. Additionally, this dosing method could improve patient adherence to the therapy.

Keywords: Amlodipine - administration & dosage, Antihypertensive Agents - administration & dosage, Atorvastatin Calcium - administration & dosage, Blood Pressure - drug effects, Case-Control Studies, Disease Management, Drug Administration Schedule, Heptanoic Acids - administration & dosage, Hypercholesterolemia - therapy, Hypertension - therapy, Patient Compliance, Pyrroles - administration & dosage