diff --git a/src/components/settings.tsx b/src/components/settings.tsx
index 29e76a7..466e349 100644
--- a/src/components/settings.tsx
+++ b/src/components/settings.tsx
@@ -119,6 +119,7 @@ const Settings = ({
   const { showDayTimeOnXAxis, yAxisMin, yAxisMax, showTemplateDay, simulationDays, displayedDays } = uiSettings;
   const showDayReferenceLines = (uiSettings as any).showDayReferenceLines ?? true;
   const showTherapeuticRange = (uiSettings as any).showTherapeuticRange ?? true;
+  const steadyStateDaysEnabled = (uiSettings as any).steadyStateDaysEnabled ?? true;
 
   const [isDiagramExpanded, setIsDiagramExpanded] = React.useState(true);
   const [isSimulationExpanded, setIsSimulationExpanded] = React.useState(true);
@@ -510,9 +511,27 @@ const Settings = ({
               />
             </div>
 
-            <div className="space-y-2">
-              <div className="flex items-center gap-2">
-                <Label className="font-medium">{t('steadyStateDays')}</Label>
+            <div className="space-y-3">
+              <div className="flex items-center gap-3">
+                <Switch
+                  id="steadyStateDaysEnabled"
+                  checked={steadyStateDaysEnabled}
+                  onCheckedChange={checked => {
+                    onUpdateUiSetting('steadyStateDaysEnabled', checked);
+                    // When toggling off, set steadyStateDays to '0'
+                    if (!checked) {
+                      updateAdvancedDirect('steadyStateDays', '0');
+                    } else {
+                      // When toggling on, set to default 7 if it's currently 0
+                      if (pkParams.advanced.steadyStateDays === '0') {
+                        updateAdvancedDirect('steadyStateDays', '7');
+                      }
+                    }
+                  }}
+                />
+                <Label htmlFor="steadyStateDaysEnabled" className="font-medium">
+                  {t('steadyStateDays')}
+                </Label>
                 <TooltipProvider>
                   <Tooltip>
                     <TooltipTrigger asChild>
@@ -530,15 +549,19 @@ const Settings = ({
                   </Tooltip>
                 </TooltipProvider>
               </div>
-              <FormNumericInput
-                value={pkParams.advanced.steadyStateDays}
-                onChange={val => updateAdvancedDirect('steadyStateDays', val)}
-                increment={1}
-                min={0}
-                max={7}
-                unit={t('unitDays')}
-                required={true}
-              />
+              {steadyStateDaysEnabled && (
+                <div className="ml-8 space-y-2">
+                  <FormNumericInput
+                    value={pkParams.advanced.steadyStateDays}
+                    onChange={val => updateAdvancedDirect('steadyStateDays', val)}
+                    increment={1}
+                    min={0}
+                    max={7}
+                    unit={t('unitDays')}
+                    required={true}
+                  />
+                </div>
+              )}
             </div>
           </CardContent>
         )}
diff --git a/src/constants/defaults.ts b/src/constants/defaults.ts
index 599b411..78f08c1 100644
--- a/src/constants/defaults.ts
+++ b/src/constants/defaults.ts
@@ -84,6 +84,7 @@ export interface UiSettings {
   displayedDays: string;
   showDayReferenceLines?: boolean;
   showTherapeuticRange?: boolean;
+  steadyStateDaysEnabled?: boolean;
   stickyChart: boolean;
 }
 
@@ -154,6 +155,7 @@ export const getDefaultState = (): AppState => ({
     simulationDays: '5',
     displayedDays: '2',
     showTherapeuticRange: true,
+    steadyStateDaysEnabled: true,
     stickyChart: false,
   }
 });