diff --git a/R/zzz.R b/R/zzz.R
index 2014072..dfd67f8 100644
--- a/R/zzz.R
+++ b/R/zzz.R
@@ -1,26 +1,29 @@
 .onLoad <- function(libname = find.package("kableExtra"), pkgname = "kableExtra") {
-  load_packages <- getOption("kableExtra.latex.load_packages", default = TRUE)
-  if (load_packages) {
-    usepackage_latex("booktabs")
-    usepackage_latex("longtable")
-    usepackage_latex("array")
-    usepackage_latex("multirow")
-    usepackage_latex("wrapfig")
-    usepackage_latex("float")
-    usepackage_latex("colortbl")
-    usepackage_latex("pdflscape")
-    usepackage_latex("tabu")
-    usepackage_latex("threeparttable")
-    usepackage_latex("threeparttablex")
-    usepackage_latex("ulem", "normalem")
-    usepackage_latex("makecell")
-    usepackage_latex("xcolor")
+  if (knitr::is_latex_output()) {
+    load_packages <- getOption("kableExtra.latex.load_packages", default = TRUE)
+    if (load_packages) {
+      usepackage_latex("booktabs")
+      usepackage_latex("longtable")
+      usepackage_latex("array")
+      usepackage_latex("multirow")
+      usepackage_latex("wrapfig")
+      usepackage_latex("float")
+      usepackage_latex("colortbl")
+      usepackage_latex("pdflscape")
+      usepackage_latex("tabu")
+      usepackage_latex("threeparttable")
+      usepackage_latex("threeparttablex")
+      usepackage_latex("ulem", "normalem")
+      usepackage_latex("makecell")
+      usepackage_latex("xcolor")
+    }
   }
   auto_format <- getOption("kableExtra.auto_format", default = TRUE)
   if (auto_format) auto_set_format()
   if (!is.null(rmarkdown::metadata$output) &&
       rmarkdown::metadata$output %in% c(
-        "ioslides_presentation", "slidy_presentation"
+        "ioslides_presentation", "slidy_presentation",
+        "gitbook", "radix_article"
       )) {
     options(kableExtra.html.bsTable = TRUE)
   }