diff --git a/mmc.c b/mmc.c
index 6c56387..4c09b79 100644
--- a/mmc.c
+++ b/mmc.c
@@ -150,7 +150,7 @@ static struct Command commands[] = {
 	  NULL
 	},
 	{ do_sanitize, -1,
-	  "sanitize", "<device>\n"
+	  "sanitize", "<device> [timeout_ms]\n"
 		"Send Sanitize command to the <device>.\nThis will delete the unmapped memory region of the device.",
 	  NULL
 	},
diff --git a/mmc_cmds.c b/mmc_cmds.c
index 3337ded..9e0571f 100644
--- a/mmc_cmds.c
+++ b/mmc_cmds.c
@@ -1986,12 +1986,16 @@ int do_sanitize(int nargs, char **argv)
 {
 	int fd, ret;
 	char *device;
+	unsigned int timeout = 0;
 
-	if (nargs != 2) {
-		fprintf(stderr, "Usage: mmc sanitize </path/to/mmcblkX>\n");
+	if (nargs != 2 && nargs != 3) {
+		fprintf(stderr, "Usage: mmc sanitize </path/to/mmcblkX> [timeout_in_ms]\n");
 		exit(1);
 	}
 
+	if (nargs == 3)
+		timeout = strtol(argv[2], NULL, 10);
+
 	device = argv[1];
 
 	fd = open(device, O_RDWR);
@@ -2000,7 +2004,7 @@ int do_sanitize(int nargs, char **argv)
 		exit(1);
 	}
 
-	ret = write_extcsd_value(fd, EXT_CSD_SANITIZE_START, 1, 0);
+	ret = write_extcsd_value(fd, EXT_CSD_SANITIZE_START, 1, timeout);
 	if (ret) {
 		fprintf(stderr, "Could not write 0x%02x to EXT_CSD[%d] in %s\n",
 			1, EXT_CSD_SANITIZE_START, device);