Comparison of cocaine alone or with adrenaline on nasal mucosal blood flow

Cocaine is commonly used in ENT practice for its vasoconstrictor and anaesthetic properties. It is sometimes combined with adrenaline. The laser Doppler Flowmeter was used to compare the effect of 5 per cent cocaine alone or with adrenaline (1 in 1,000) on nasal mucosal blood flow. The results show an average fall in blood flow of 76.7 per cent for cocaine with adrenaline, compared to 61.2 per cent with cocaine alone. The difference is significant (P less than 0.05). The time taken for the blood flow to fall was an average of 131 s and 160 s respectively. These differences are not significant.