diff --git a/biscuit/apps/chronos/forms.py b/biscuit/apps/chronos/forms.py
index e0076d08fa3b44d2e3e6775e551bef60217e09fa..85d7b66f6681b013f6683af0860c01cba41fe1c9 100644
--- a/biscuit/apps/chronos/forms.py
+++ b/biscuit/apps/chronos/forms.py
@@ -25,7 +25,11 @@ class LessonSubstitutionForm(forms.ModelForm):
 
     def __init__(self, *args, **kwargs):
         super().__init__(*args, **kwargs)
+
         self.fields['lesson_period'].queryset = LessonPeriod.objects.all()
         self.fields['subject'].queryset = Subject.objects.all()
         self.fields['teachers'].queryset = Person.objects.all()
         self.fields['room'].queryset = Room.objects.all()
+
+        self.fields['week'].disabled = True
+        self.fields['lesson_period'].disabled = True