Comparative bioavailability of slow release diclofenac (Voveran SR) with enteric coated tablet and internationally used Voltaren Retard.

The objective of the study was to compare the enteric coated diclofenac sodium (Voveran), the slow release formulation developed in India (Voveran SR) and the internationally marketed formulation Voltaren Retard. Ten healthy volunteers were administered 100 mg each of the three formulations in a three-way crossover fashion. Blood samples were collected over 24 hours following administration of the drug; plasma levels of unchanged drug were determined by gas chromatography. Pharmacokinetic parameters for the three formulations were compared. The extent of the drug available from the three formulations was the same as the mean AUC values were not significantly different. Cmax and MRT values for the two slow release formulations were comparable but were significantly different from the values obtained with the enteric coated formulation. Tmax values for the two slow release formulations were similar while the enteric coated tablet had faster time to peak. Voveran SR is comparable to Voltaren Retard and has the distinct advantage of a slow release formulation in that its Cmax is much lower and levels are maintained over 12 hours and detectable upto 24 hours. This slow release formulation will offer clinical advantages of better compliance, relief of early morning symptoms and better tolerability over long term usage.

A multi-centre comparative study of diclofenac sodium and a dipyrone/spasmolytic combination, and a single-centre comparative study of diclofenac sodium and pethidine in renal colic patients in India.

A single-blind, randomized clinical trial was carried out to compare the analgesic effectiveness in patients with renal colic of single intramuscular doses of diclofenac sodium (75 mg) versus a dipyrone (1 g)/spasmolytics combination, and diclofenac sodium (75 mg) versus pethidine (75 mg). The first study involved three centres, the second study one centre. In total, 107 patients were treated with diclofenac sodium, 85 with dipyrone/spasmolytics, and 25 with pethidine. Assessments were made during the first hour after drug administration of the degree of pain relief, the severity of pain using a visual analogue scale, and the duration of analgesia. A global assessment of treatment efficacy was made by the participating physicians at the end of the study period. Patients treated with diclofenac sodium showed an earlier onset of analgesia and a higher incidence of total pain relief compared to those treated with dipyrone/spasmolytics or pethidine. Although the mean duration of analgesia was only slightly greater in the diclofenac sodium group than in the dipyrone/spasmolytics group, a significantly longer effect was seen when diclofenac sodium was compared with pethidine (p less than 0.01). Pain severity assessments revealed that diclofenac sodium caused a significantly greater improvement in pain after 60 minutes compared to dipyrone/spasmolytics (p less than 0.05) and after 30 minutes compared to pethidine (p less than 0.05). Global efficacy assessments by the physician rated diclofenac sodium as significantly superior to dipyrone/spasmolytics (p less than 0.01) and pethidine (p less than 0.001). Moreover, diclofenac sodium was better tolerated than either of the comparative treatments. The results indicate that intramuscular diclofenac sodium is a useful alternative to the drugs commonly used in India in the treatment of renal colic.