diff --git a/Sources/Sentry/SentryUncaughtNSExceptions.m b/Sources/Sentry/SentryUncaughtNSExceptions.m
--- a/Sources/Sentry/SentryUncaughtNSExceptions.m
+++ b/Sources/Sentry/SentryUncaughtNSExceptions.m
@@ -40,34 +40,37 @@
 #    if SENTRY_TEST || SENTRY_TEST_CI
 #        pragma clang diagnostic ignored "-Wunused-variable"
 #    endif
-    // AppKit calls _crashOnException: when an exception is caught during CATransaction flush
-    // or view layout, bypassing reportException: entirely. Depending on macOS version, AppKit
-    // may call the class method +[NSApplication _crashOnException:] or the instance method
-    // -[NSApp _crashOnException:], so we swizzle both.
-    SEL selector = NSSelectorFromString(@"_crashOnException:");
+    static dispatch_once_t onceToken;
+    dispatch_once(&onceToken, ^{
+        // AppKit calls _crashOnException: when an exception is caught during CATransaction flush
+        // or view layout, bypassing reportException: entirely. Depending on macOS version, AppKit
+        // may call the class method +[NSApplication _crashOnException:] or the instance method
+        // -[NSApp _crashOnException:], so we swizzle both.
+        SEL selector = NSSelectorFromString(@"_crashOnException:");
 
-    SentrySwizzleClassMethod(NSApplication, selector, SentrySWReturnType(void),
-        SentrySWArguments(NSException * exception), SentrySWReplacement({
-            [SentryUncaughtNSExceptions capture:exception];
+        SentrySwizzleClassMethod(NSApplication, selector, SentrySWReturnType(void),
+            SentrySWArguments(NSException * exception), SentrySWReplacement({
+                [SentryUncaughtNSExceptions capture:exception];
 #    if SENTRY_TEST || SENTRY_TEST_CI
-            // Don't call the original in tests as it would abort() the process.
-            swizzleInfo.originalCalled = YES;
+                // Don't call the original in tests as it would abort() the process.
+                swizzleInfo.originalCalled = YES;
 #    else
-            return SentrySWCallOriginal(exception);
+                return SentrySWCallOriginal(exception);
 #    endif
-        }));
+            }));
 
-    SentrySwizzleInstanceMethod(NSApplication, selector, SentrySWReturnType(void),
-        SentrySWArguments(NSException * exception), SentrySWReplacement({
-            [SentryUncaughtNSExceptions capture:exception];
+        SentrySwizzleInstanceMethod(NSApplication, selector, SentrySWReturnType(void),
+            SentrySWArguments(NSException * exception), SentrySWReplacement({
+                [SentryUncaughtNSExceptions capture:exception];
 #    if SENTRY_TEST || SENTRY_TEST_CI
-            // Don't call the original in tests as it would abort() the process.
-            swizzleInfo.originalCalled = YES;
+                // Don't call the original in tests as it would abort() the process.
+                swizzleInfo.originalCalled = YES;
 #    else
-            return SentrySWCallOriginal(exception);
+                return SentrySWCallOriginal(exception);
 #    endif
-        }),
-        SentrySwizzleModeOncePerClassAndSuperclasses, (void *)selector);
+            }),
+            SentrySwizzleModeOncePerClassAndSuperclasses, (void *)selector);
+    });
 #    pragma clang diagnostic pop
 }
 

diff --git a/Tests/SentryTests/Integrations/SentryCrash/SentryUncaughtNSExceptionsTests.swift b/Tests/SentryTests/Integrations/SentryCrash/SentryUncaughtNSExceptionsTests.swift
--- a/Tests/SentryTests/Integrations/SentryCrash/SentryUncaughtNSExceptionsTests.swift
+++ b/Tests/SentryTests/Integrations/SentryCrash/SentryUncaughtNSExceptionsTests.swift
@@ -51,7 +51,31 @@
 
         XCTAssertTrue(wasUncaughtExceptionHandlerCalled)
     }
+    
+    func testSwizzleNSApplicationCrashOnException_whenCalledMultipleTimes_shouldCaptureClassMethodOnce() throws {
+        let crashReporter = SentryDependencyContainer.sharedInstance().crashReporter
 
+        defer {
+            crashReporter.uncaughtExceptionHandler = nil
+            wasUncaughtExceptionHandlerCalled = false
+            uncaughtExceptionHandlerCallCount = 0
+        }
+
+        wasUncaughtExceptionHandlerCalled = false
+        uncaughtExceptionHandlerCallCount = 0
+        crashReporter.uncaughtExceptionHandler = uncaughtExceptionHandler
+
+        SentryUncaughtNSExceptions.swizzleNSApplicationCrashOnException()
+        SentryUncaughtNSExceptions.swizzleNSApplicationCrashOnException()
+
+        // Call the class method +[NSApplication _crashOnException:].
+        // In tests, SentrySWCallOriginal is skipped so this won't abort().
+        NSApplication.perform(NSSelectorFromString("_crashOnException:"), with: uncaughtInternalInconsistencyException)
+
+        XCTAssertTrue(wasUncaughtExceptionHandlerCalled)
+        XCTAssertEqual(1, uncaughtExceptionHandlerCallCount)
+    }
+
     func testSwizzleNSApplicationCrashOnException_instanceMethod() throws {
         let crashReporter = SentryDependencyContainer.sharedInstance().crashReporter
 
@@ -108,10 +132,12 @@
 // We need to declare this on the file level because otherwise we get the error:
 // A C function pointer cannot be formed from a closure that captures context.
 var wasUncaughtExceptionHandlerCalled = false
+var uncaughtExceptionHandlerCallCount = 0
 func uncaughtExceptionHandler(exception: NSException) {
     XCTAssertEqual(uncaughtInternalInconsistencyException.name, exception.name)
     XCTAssertEqual(uncaughtInternalInconsistencyException.reason, exception.reason)
     wasUncaughtExceptionHandlerCalled = true
+    uncaughtExceptionHandlerCallCount += 1
 }
 
 let uncaughtInternalInconsistencyException = NSException(name: .internalInconsistencyException, reason: "reason", userInfo: nil)