diff --git a/src/pam_panic/pam_panic_authdevice.h b/src/pam_panic/pam_panic_authdevice.h
index 3302a34..31757ef 100644
--- a/src/pam_panic/pam_panic_authdevice.h
+++ b/src/pam_panic/pam_panic_authdevice.h
@@ -5,8 +5,12 @@ DATE :         2018-03-27T02:34:08+02:00
 LICENSE :      GNU-GPLv3
 */
 
+#ifndef PAM_PANIC_AUTHDEVICE_H
+#define PAM_PANIC_AUTHDEVICE_H
 #include "../config.h"
 #include <stdint.h>
 #include <security/pam_modules.h>
 
 int authDevice(pam_handle_t *pamh, char *allowed, char *rejected, char *serious_dev, int8_t bSerious, int8_t bReboot, int8_t bPoweroff);
+
+#endif
diff --git a/src/pam_panic/pam_panic_password.h b/src/pam_panic/pam_panic_password.h
index 356d73e..d39d8b1 100644
--- a/src/pam_panic/pam_panic_password.h
+++ b/src/pam_panic/pam_panic_password.h
@@ -5,6 +5,9 @@ DATE :         2018-03-27T02:34:08+02:00
 LICENSE :      GNU-GPLv3
 */
 
+#ifndef PAM_PANIC_PASSWORD_H
+#define PAM_PANIC_PASSWORD_H
+
 #include "../config.h"
 #include <stdint.h>
 #include <security/pam_modules.h>
@@ -16,5 +19,4 @@ LICENSE :      GNU-GPLv3
 
 int authPassword(pam_handle_t *pamh, char *serious_dev, int8_t bSerious, int8_t bReboot, int8_t bPoweroff);
 
-
-
+#endif
diff --git a/src/pam_panic/pam_panic_reject.h b/src/pam_panic/pam_panic_reject.h
index de44350..6b7308b 100644
--- a/src/pam_panic/pam_panic_reject.h
+++ b/src/pam_panic/pam_panic_reject.h
@@ -5,7 +5,11 @@ DATE :         2018-03-27T02:34:08+02:00
 LICENSE :      GNU-GPLv3
 */
 
+#ifndef PAM_PANIC_REJECT_H
+#define PAM_PANIC_REJECT_H
 #include "../config.h"
 #include <stdint.h>
 
 int reject(char *serious_dev, int8_t bSerious, int8_t bReboot, int8_t bPoweroff);
+
+#endif