diff --git a/R/auc.R b/R/auc.R
index 9f3c7571..160ac56f 100644
--- a/R/auc.R
+++ b/R/auc.R
@@ -12,6 +12,10 @@
 #'
 #' If all conc input are zero, then the AU(M)C is zero.
 #'
+#' You probably do not want to call `pk.calc.auxc()`.  Usually, you will call
+#' one of the other functions for calculating AUC like `pk.calc.auc.last()`,
+#' `pk.calc.auc.inf.obs()`, etc.
+#'
 #' @inheritParams assert_conc_time
 #' @inheritParams assert_intervaltime_single
 #' @inheritParams choose_interval_method
diff --git a/man/pk.calc.auxc.Rd b/man/pk.calc.auxc.Rd
index 7ee80ab8..b1447d32 100644
--- a/man/pk.calc.auxc.Rd
+++ b/man/pk.calc.auxc.Rd
@@ -120,6 +120,10 @@ Extrapolation beyond Clast occurs using the half-life and Clast,obs;
 Clast,pred is not yet supported.
 
 If all conc input are zero, then the AU(M)C is zero.
+
+You probably do not want to call \code{pk.calc.auxc()}.  Usually, you will call
+one of the other functions for calculating AUC like \code{pk.calc.auc.last()},
+\code{pk.calc.auc.inf.obs()}, etc.
 }
 \section{Functions}{
 \itemize{