Objective
To evaluate the effect of oral sildenafil citrate (Viagra^Ⱂ) on erectile dysfunction following spinal cord injury.

Method
Seventy nine male patients with erectile dysfunction after spinal cord injury, who were free from contraindications, received 50 mg of sildenafil. Visual-analogue erection scale (VAES) was used to evaluate the rigidity of penis before and after the medication. In addition, the duration of erection and side effects of sildenafil were evaluated.

Results
Mean VAES score showed a statistically significant increase after the medication from 5.6 to 7.5 (p=0.000). The mean duration of erection also increased from 3.4 minutes to 27.1 minutes after medication (p=0.000). Sixty seven patients (84.8%) reported improved erection with 50 mg of sildenafil and sixty one patients (77.2%) reported rigid erection enough for sexual intercourse. Ten patients (12.7%) reported side effects: facial flushing (3), dizziness (2), headache (2), chest pain (2), and palpitation (1).

Conclusion
This study demonstrated that sildenafil is an effective medication in treating erectile dysfunction after spinal cord injury. (J Korean Acad Rehab Med 2002; 26: 306-310)