The Complementary and Alternative Medicine for Urological Symptoms (CAMUS) study was a double-blind, placebo-controlled randomized clinical trial that investigated the efficacy of a widely available phytotherapy, saw palmetto extract, at up to 3 times the standard dose on lower urinary tract symptoms attributed to benign prostatic hyperplasia (BPH) in men. Although saw palmetto fruit extract is widely used for treating lower urinary tract symptoms attributed to BPH, a well-design National Institutes of Health supported clinical trial (Avins A et al. JAMA) failed to a benefit of this treatment compared to placebo. The CAMUS study enrolled males with a peak urinary flow rate of at least 4 mL/s and an American Urological Associate Symptom Index (AUASI) score of between 8 and 24 at screening visits. Participants were randomly assigned equally to receive one, two, and then three 320 mg gelcaps daily containing a standardized saw palmetto fruit extract with dose escalations at 24 and 48 weeks; or an identical number of placebo gelcaps escalated similarly. The primary outcome was the change in AUASI score from baseline to 72 weeks. Participants were closely monitored for adverse events. The study concluded that saw palmetto extract used at up to 3 times the standard daily dose had no greater effect than placebo on improving lower urinary symptoms or other outcomes related to BPH.

The overall goal of the CAMUS study was to compare the efficacy of a widely available phytotherapy, extract of Serenoa repens, with placebo on lower urinary tract symptoms in men with BPH.

The primary outcome measure was the change in AUASI, which is a self-administered 7 item index assessing frequency of lower urinary tract symptoms, scored from baseline to 72 weeks. Participants were seen at baseline and at 12, 24, 36, 48, 60, and 72 weeks for outcome assessments. They were assessed for side effects with blood counts, basic blood chemistries, coagulation tests, electrocardiograms, and urinalyses 4 weeks after each dose increase and at end of study, including a query about adverse effects occurring within 30 days of treatment discontinuation.

Participants included males at least 45 years of age who met the following criteria: (1) peak urinary flow rate at least 4 mL/s with a voided volume of at least 125 mL and (2) AUASI score of between 8 and 24 at both screening visits.

The CAMUS study found that saw palmetto extract used at up to three times the standard daily dose, while safe and with no attributable side effects, did not reduce lower urinary symptoms or other outcomes related to BPH compared to placebo.