Healthy volunteers
Not accepted
Inclusion Criteria:- Mild to moderate hypertension (sitting DBP \> 95 - \<114 mmHg and/or SBP \> 140 - \< 160 mmHg) currently untreated. or- Previously diagnosed mild to moderate hypertension (DBP 95-114 mmHg and/or SBP 140 - 160 mmHg) well controlled on current treatment but experiencing adverse events who can be safely switched to the study treatments. or- Previously diagnosed mild to moderate hypertension (DBP 95-114 mmHg and/or SBP 140 - 160 mmHg), well controlled on current treatment, without adverse events, and willing to participate in the study. Exclusion Criteria:- Females who are pregnant, nursing or of childbearing age, unless sterilised. Subjects receiving any form of contraception are not eligible.- Subjects with a medical history of cardiac disease within 6 months (e.g. myocarditis or pericarditis, aortic stenosis, myocardial infarction, unstable angina pectoris or severe angina pectoris). - Subjects with history or evidence of congestive heart failure- Subjects with evidence of clinically important arrhythmia or conduction disturbances requiring treatment.- Subjects with severe liver disease (liver enzymes twice the upper limit of "normal") or other gastrointestinal (GI) tract diseases including inflammatory bowel disease or Crohns disease- Subjects with lactose intolerance.- Subjects with renal diseases (creatinine \> 1.5 mg/dL), which could alter the absorption, metabolism or excretion of the study drugs.- Subjects with Type I diabetes. - Subjects taking drugs which may interfere with the metabolism of nifedipine (cimetidine, ranitidine, quinidine, digoxin, rifampicin, diltiazem, cisapride, quinupristin/dalfopristin, cyclosporin, phenytoin or other antiepileptic drugs,).- Subjects suffering from secondary or malignant hypertension.- Subjects with any known contraindication (e.g. hypersensitivity) to nifedipine or other calcium channel blockers of the dihydropyridine class.- Subjects with previously known clinically significant abnormalities of laboratory tests that might suggest further investigation.- Subjects with a resting heart rate \< 50 bpm or \> 100 bpm.- Subjects with a history of drug and/or alcohol abuse.- Subjects unwilling to comply with the protocol.- Subjects who have participated in another clinical trial within the last month.- Subjects with neurologic or psychiatric illness requiring medication (e.g. tricyclic antidepressants, MAO inhibitors).- Subjects with clinical evidence of ongoing or recent (within the last year) stroke or transient ischemic attacks.- Subjects with pre-existing severe gastrointestinal or oesophageal constriction or narrowing.