Yes, Voltaren (diclofenac), a non steroidal anti-inflammatory drug (NSAID) can indirectly cause high blood pressure. Fluid retention and edema have been observed in some patients taking diclofenac. This can cause blood pressure to rise. Therefore, as with other NSAIDs, diclofenac should be used with caution in patients with a history of cardiac decompensation, hypertension, or other conditions predisposing to fluid retention. Another mechanism which may contribute to high blood pressure is the fact that diclofenac can lead to a reduction in renal blood flow or blood volume, where renal prostaglandins have a supportive role in the maintenance of renal perfusion. Stop taking it and see your doctor.