VA106483 is intended to be used as a treatment for patients suffering from nocturia (defined as waking to urinate at least once per night between periods of sleep). Nocturia is a condition that often worsens as sufferers get older. This may be due to an over-active bladder muscle, the bladder being able to hold less urine at night-time or over production of urine in the bladder at night. Some of the treatments available for nocturia have side-effects which make them unsuitable for elderly patients. These side-effects have not been seen in studies with VA106483, which makes it potentially suitable for treating elderly patients.~Nocturia is commonly associated with Benign Prostatic Hypertrophy (or BPH, a non-cancerous enlargement of the prostate gland, which often results in problems passing water). Of the patients who suffer from BPH, an estimated 40-85% experience the symptoms of waking at night to pass water.~Treatments which are commonly prescribed for BPH include alpha-blockers which work by improving urine flow by a muscle relaxant effect. Alpha-blockers are known to cause hypotension (lowering of blood pressure which can cause dizziness in some patients) . Since it is likely that subjects may be co-prescribed VA106483 and alpha-blockers, the purpose of this study is to determine that giving VA106483 does not increase the hypotensive effects of alpha-blockers
The main purpose of this study is to investigate whether the hypotensive effects of an alpha-blocker are increased when VA106483 is given at the same time.