Caffeine: does it affect your bladder?

Patients with symptoms of frequency and urgency often complain that their symptoms are exacerbated by tea or coffee. A series of 20 women with confirmed detrusor instability and 10 asymptomatic women were given 200 mg of caffeine citrate and urodynamic studies were performed. In the group with detrusor instability there was a statistically significant increase in detrusor pressure on bladder filling following administration of caffeine, but no difference in volume at first contraction, height of contraction or bladder capacity. Normal women had no abnormality on cystometry.