Randomized, controlled clinical trial of safety and plasma concentrations of diclofenac in healthy neonatal foals after repeated topical application of 1% diclofenac sodium cream.

The research article explores the effects and safety of twice-daily application of a diclofenac sodium cream on newborn foals. The findings suggest that the cream is safe for usage on foals as it has little systemic absorption and does not produce any adverse effects.

Study Design and Procedure

• In this study, twelve 2 to 14-day old healthy Arabian and Arabian-pony cross neonatal foals were used. The foals were divided into two groups – one group received the 1% diclofenac sodium cream and the other group received an equivalent amount of placebo cream.
• The cream, containing 7.3 mg of diclofenac sodium, was applied to a 5 cm square of shaved skin over the anterolateral aspect of the left tarsometatarsal region every 12 hours for 7 days.
• Physical examinations, Complete Blood Count (CBC), serum biochemistry, urinalysis, gastric endoscopy and ultrasonographic examination of the kidneys and right dorsal colon were done both before and after the cream application to ensure safety of the cream.

Measurement and Results

• Venous blood samples were collected at predefined intervals after the application of the diclofenac cream. The plasma diclofenac concentrations were then measured using liquid chromatography-mass spectrometry.
• The results determined that none of the foals developed any adverse effects attributed to diclofenac application, and there were no significant differences in the evaluated variables between the two groups.
• The measurements also showed that the plasma diclofenac concentrations peaked rapidly after the medication was applied, reaching a maximum of less than 1 ng/mL within 2 hours, and then decreased rapidly after the application stopped.

Conclusions and Clinical Implications

• The study concluded that the topical application of 1% diclofenac sodium cream to foals is safe. The low plasma concentrations of diclofenac suggested minimal systemic absorption, which means the cream does not appear to pass substantially into the circulatory system of the foals.
• The findings from this research may encourage practitioners to consider using this medication to treat focal areas of pain and inflammation in newborn foals.