Aims: This study was undertaken to compare the analgesic onset of voltfast and diclofenac potassium in patients after extraction of teeth. Materials and methods: One hundred fifty patients were enrolled in this study and randomly divided into two groups. Group 1 received sachets of oral diclofenac potassium (Voltfast) and group 2 received entric coated of diclofenac sodium (Cataflam) after extraction of teeth. The patients reported their pain relief in a questionnaire after the tooth extraction. The patient was instructed to take the drug as prescribed as the effect of local anesthesia begin to wear off and pain start. To evaluate the onset of the two drugs, the patients were asked to report if they had any problem using the drug. Results: seventy five patients received voltfast and cataflam seventy five patients received for relief of pain. The pain relief in both groups was efficient with statistically significant difference between the two groups. Conclusions: Oral diclofenac is an effective treatment for moderate to severe postoperative pain. Significantly more participants experienced a faster onset of pain relief with voltfast than with cataflam.