diff --git a/src/domain/switch.rs b/src/domain/switch.rs
index e3b99e8..330cc17 100644
--- a/src/domain/switch.rs
+++ b/src/domain/switch.rs
@@ -68,7 +68,9 @@ where
             line.to_string()
         } else if let Some(cur_sections) = current_sections.clone() {
             let trimmed_line = line.trim_start_matches(['#', ' ']);
-            if should_enable_variable(&choose_sections, &cur_sections) {
+            if !is_variables(trimmed_line) {
+                line.to_string()
+            } else if should_enable_variable(&choose_sections, &cur_sections) {
                 String::from(trimmed_line)
             } else if should_disable_variable(&choose_sections, &cur_sections) {
                 format!("# {}", trimmed_line)
@@ -87,6 +89,15 @@ where
     writer.flush().map_err(|_| Error::WriteData)
 }
 
+fn is_variables(trimmed_line: &str) -> bool {
+    trimmed_line
+        .chars()
+        .filter(|ch| (*ch != '_' && ch.is_ascii_punctuation()) || ch.is_whitespace())
+        .enumerate()
+        .find(|(_, ch)| *ch == '=')
+        .map_or(false, |(i, _)| i == 0)
+}
+
 fn is_section_end(line: &str) -> bool {
     line.trim().is_empty()
 }
@@ -274,5 +285,20 @@ mod tests {
                 &[Section::with_namespace("debug", "off")]
             ));
         }
+
+        #[test]
+        fn should_check_line_on_variable() {
+            let test_cases = [
+                ("VAR=10", true),
+                ("THIS_IS_MY_VAR='hello world'", true),
+                ("hello world", false),
+                ("staging/production", false),
+                ("staging/production=value", false),
+            ];
+
+            for (input, expected) in test_cases {
+                assert_eq!(is_variables(input), expected);
+            }
+        }
     }
 }
diff --git a/test_data/all_env b/test_data/all_env
index 1583d32..53785ee 100644
--- a/test_data/all_env
+++ b/test_data/all_env
@@ -2,6 +2,7 @@ VITE_STRIPE_PK=
 VITE_SENTRY_ENABLED=
 VITE_SENTRY_DSN=
 ### local,staging
+# staging/production
 VITE_SENTRY_ENV=staging
 ### prod
 VITE_SENTRY_ENV=production
diff --git a/test_data/base_env b/test_data/base_env
index 6888eb6..40bfff7 100644
--- a/test_data/base_env
+++ b/test_data/base_env
@@ -2,6 +2,7 @@ VITE_STRIPE_PK=
 VITE_SENTRY_ENABLED=
 VITE_SENTRY_DSN=
 ### local,staging
+# staging/production
 # VITE_SENTRY_ENV=staging
 ### prod
 # VITE_SENTRY_ENV=production
diff --git a/test_data/should_enable_local b/test_data/should_enable_local
index d6e4df7..9e8082f 100644
--- a/test_data/should_enable_local
+++ b/test_data/should_enable_local
@@ -2,6 +2,7 @@ VITE_STRIPE_PK=
 VITE_SENTRY_ENABLED=
 VITE_SENTRY_DSN=
 ### local,staging
+# staging/production
 VITE_SENTRY_ENV=staging
 ### prod
 # VITE_SENTRY_ENV=production
diff --git a/test_data/should_enable_staging b/test_data/should_enable_staging
index a6b48fc..4456cea 100644
--- a/test_data/should_enable_staging
+++ b/test_data/should_enable_staging
@@ -2,6 +2,7 @@ VITE_STRIPE_PK=
 VITE_SENTRY_ENABLED=
 VITE_SENTRY_DSN=
 ### local,staging
+# staging/production
 VITE_SENTRY_ENV=staging
 ### prod
 # VITE_SENTRY_ENV=production
diff --git a/test_data/should_use_debug_in_staging b/test_data/should_use_debug_in_staging
index 6681dda..91fe341 100644
--- a/test_data/should_use_debug_in_staging
+++ b/test_data/should_use_debug_in_staging
@@ -2,6 +2,7 @@ VITE_STRIPE_PK=
 VITE_SENTRY_ENABLED=
 VITE_SENTRY_DSN=
 ### local,staging
+# staging/production
 VITE_SENTRY_ENV=staging
 ### prod
 # VITE_SENTRY_ENV=production
diff --git a/test_data/should_use_staging_db_in_local b/test_data/should_use_staging_db_in_local
index 8cb508a..04dc10a 100644
--- a/test_data/should_use_staging_db_in_local
+++ b/test_data/should_use_staging_db_in_local
@@ -2,6 +2,7 @@ VITE_STRIPE_PK=
 VITE_SENTRY_ENABLED=
 VITE_SENTRY_DSN=
 ### local,staging
+# staging/production
 VITE_SENTRY_ENV=staging
 ### prod
 # VITE_SENTRY_ENV=production