diff --git a/tests/testthat.R b/tests/testthat.R
index ae7d97f..5a60cdc 100644
--- a/tests/testthat.R
+++ b/tests/testthat.R
@@ -1,3 +1,5 @@
+data.table::setDTthreads(2) #throttle data.table for CRAN
+
 library(testthat)
 library(posologyr)
 
diff --git a/vignettes/a_posteriori_dosing.Rmd b/vignettes/a_posteriori_dosing.Rmd
index 2fde305..9d30d6f 100644
--- a/vignettes/a_posteriori_dosing.Rmd
+++ b/vignettes/a_posteriori_dosing.Rmd
@@ -15,6 +15,10 @@ knitr::opts_chunk$set(
 set.seed(1)
 ```
 
+```{r chunkname, echo=-1}
+data.table::setDTthreads(2)
+```
+
 ```{r setup}
 library(posologyr)
 ```
diff --git a/vignettes/a_priori_dosing.Rmd b/vignettes/a_priori_dosing.Rmd
index 3b0fdda..fcd8c7f 100644
--- a/vignettes/a_priori_dosing.Rmd
+++ b/vignettes/a_priori_dosing.Rmd
@@ -15,6 +15,10 @@ knitr::opts_chunk$set(
 set.seed(1)
 ```
 
+```{r chunkname, echo=-1}
+data.table::setDTthreads(2)
+```
+
 ```{r setup}
 library(posologyr)
 ```
diff --git a/vignettes/auc_based_dosing.Rmd b/vignettes/auc_based_dosing.Rmd
index be615f4..dfdf87d 100644
--- a/vignettes/auc_based_dosing.Rmd
+++ b/vignettes/auc_based_dosing.Rmd
@@ -15,6 +15,10 @@ knitr::opts_chunk$set(
 set.seed(1)
 ```
 
+```{r chunkname, echo=-1}
+data.table::setDTthreads(2)
+```
+
 ```{r setup}
 library(posologyr)
 ```
diff --git a/vignettes/multiple_endpoints.Rmd b/vignettes/multiple_endpoints.Rmd
index 83c09c7..4d5978c 100644
--- a/vignettes/multiple_endpoints.Rmd
+++ b/vignettes/multiple_endpoints.Rmd
@@ -14,6 +14,10 @@ knitr::opts_chunk$set(
 )
 ```
 
+```{r chunkname, echo=-1}
+data.table::setDTthreads(2)
+```
+
 ```{r setup}
 library(posologyr)
 ```