diff --git a/CHANGELOG.md b/CHANGELOG.md
index 5bcf27301a..789871c4a6 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,6 +8,7 @@
     Bug #5483: AutoCalc flag is not used to calculate spells cost
     Bug #6066: addtopic "return" does not work from within script. No errors thrown
     Bug #6101: Disarming trapped unlocked owned objects isn't considered a crime
+    Bug #6107: Fatigue is incorrectly recalculated when fortify effect is applied or removed
     Bug #6115: Showmap overzealous matching
 
 0.47.0
diff --git a/apps/openmw/mwmechanics/actors.cpp b/apps/openmw/mwmechanics/actors.cpp
index e62d686ee2..e9eab2991b 100644
--- a/apps/openmw/mwmechanics/actors.cpp
+++ b/apps/openmw/mwmechanics/actors.cpp
@@ -826,7 +826,7 @@ namespace MWMechanics
 
         DynamicStat<float> magicka = creatureStats.getMagicka();
         float diff = (static_cast<int>(magickaFactor*intelligence)) - magicka.getBase();
-        float currentToBaseRatio = (magicka.getCurrent() / magicka.getBase());
+        float currentToBaseRatio = magicka.getBase() > 0 ? magicka.getCurrent() / magicka.getBase() : 0;
         magicka.setModified(magicka.getModified() + diff, 0);
         magicka.setCurrent(magicka.getBase() * currentToBaseRatio, false, true);
         creatureStats.setMagicka(magicka);
diff --git a/apps/openmw/mwmechanics/creaturestats.cpp b/apps/openmw/mwmechanics/creaturestats.cpp
index c6561af961..1ff44fcbb0 100644
--- a/apps/openmw/mwmechanics/creaturestats.cpp
+++ b/apps/openmw/mwmechanics/creaturestats.cpp
@@ -159,7 +159,7 @@ namespace MWMechanics
                 float diff = (strength+willpower+agility+endurance) - fatigue.getBase();
                 float currentToBaseRatio = fatigue.getBase() > 0 ? (fatigue.getCurrent() / fatigue.getBase()) : 0;
                 fatigue.setModified(fatigue.getModified() + diff, 0);
-                fatigue.setCurrent(fatigue.getBase() * currentToBaseRatio);
+                fatigue.setCurrent(fatigue.getBase() * currentToBaseRatio, false, true);
                 setFatigue(fatigue);
             }
         }