diff --git a/include/boost/math/special_functions/detail/bessel_ik.hpp b/include/boost/math/special_functions/detail/bessel_ik.hpp
index badb70dee..2ffb0f060 100644
--- a/include/boost/math/special_functions/detail/bessel_ik.hpp
+++ b/include/boost/math/special_functions/detail/bessel_ik.hpp
@@ -18,7 +18,6 @@
 #include <boost/math/constants/constants.hpp>
 #include <boost/math/policies/error_handling.hpp>
 #include <boost/math/tools/config.hpp>
-#include <iostream>
 
 // Modified Bessel functions of the first and second kind of fractional order