diff --git a/autotests/folding/highlight.tex.fold b/autotests/folding/highlight.tex.fold
--- a/autotests/folding/highlight.tex.fold
+++ b/autotests/folding/highlight.tex.fold
@@ -273,3 +273,7 @@
 % Close brackets correctly in some commands (see bug #415384)
 \input{\a{}}
 \cites{ text { text } text }
+
+% Parentheses within [ ... ] (see bug #418979)
+\cite[eq. (1.1)]{some_reference}
+\cite[eq. \(x^n + y^n = z^n\)]{some reference}
diff --git a/autotests/html/highlight.tex.html b/autotests/html/highlight.tex.html
--- a/autotests/html/highlight.tex.html
+++ b/autotests/html/highlight.tex.html
@@ -279,4 +279,8 @@
 <span style="color:#898887;">% Close brackets correctly in some commands (see bug #415384)</span>
 <span style="color:#644a9b;">\input</span>{<span style="color:#644a9b;">\a</span>{}}
 <span style="font-weight:bold;">\cites</span>{<span style="color:#0095ff;font-weight:bold;"> text </span>{<span style="color:#0095ff;font-weight:bold;"> text </span>}<span style="color:#0095ff;font-weight:bold;"> text </span>}
+
+<span style="color:#898887;">% Parentheses within [ ... ] (see bug #418979)</span>
+<span style="font-weight:bold;">\cite</span>[eq. (1.1)]{<span style="color:#0095ff;font-weight:bold;">some_reference</span>}
+<span style="font-weight:bold;">\cite</span>[eq. <span style="color:#ff5500;">\(x^n + y^n = z^n\)</span>]{<span style="color:#0095ff;font-weight:bold;">some reference</span>}
 </pre></body></html>
diff --git a/autotests/input/highlight.tex b/autotests/input/highlight.tex
--- a/autotests/input/highlight.tex
+++ b/autotests/input/highlight.tex
@@ -273,3 +273,7 @@
 % Close brackets correctly in some commands (see bug #415384)
 \input{\a{}}
 \cites{ text { text } text }
+
+% Parentheses within [ ... ] (see bug #418979)
+\cite[eq. (1.1)]{some_reference}
+\cite[eq. \(x^n + y^n = z^n\)]{some reference}
diff --git a/autotests/reference/highlight.tex.ref b/autotests/reference/highlight.tex.ref
--- a/autotests/reference/highlight.tex.ref
+++ b/autotests/reference/highlight.tex.ref
@@ -273,3 +273,7 @@
 <Comment>% Close brackets correctly in some commands (see bug #415384)</Comment><br/>
 <Macro>\input</Macro><Normal Text>{</Normal Text><Macro>\a</Macro><Normal Text>{}}</Normal Text><br/>
 <Structure>\cites</Structure><Normal Text>{</Normal Text><Environment> text </Environment><Normal Text>{</Normal Text><Environment> text </Environment><Normal Text>}</Normal Text><Environment> text </Environment><Normal Text>}</Normal Text><br/>
+<Normal Text></Normal Text><br/>
+<Comment>% Parentheses within [ ... ] (see bug #418979)</Comment><br/>
+<Structure>\cite</Structure><Normal Text>[eq. (1.1)]{</Normal Text><Reference>some_reference</Reference><Normal Text>}</Normal Text><br/>
+<Structure>\cite</Structure><Normal Text>[eq. </Normal Text><Math>\(x^n + y^n = z^n\)</Math><Normal Text>]{</Normal Text><Reference>some reference</Reference><Normal Text>}</Normal Text><br/>
diff --git a/data/syntax/latex.xml b/data/syntax/latex.xml
--- a/data/syntax/latex.xml
+++ b/data/syntax/latex.xml
@@ -5,7 +5,7 @@
     <!ENTITY envname "[a-zA-Z]+\*?">
     <!ENTITY regionmarker "&#037;\s*(?:BEGIN|END)">
 ]>
-<language name="LaTeX" version="12" section="Markup" kateversion="5.0" priority="10" extensions="*.tex;*.ltx;*.dtx;*.sty;*.cls;*.bbx;*.cbx;*.lbx;*.tikz;*.pgf" mimetype="text/x-tex" casesensitive="1" author="Jeroen Wijnhout (Jeroen.Wijnhout@kdemail.net)+Holger Danielsson (holger.danielsson@versanet.de)+Michel Ludwig (michel.ludwig@kdemail.net)+Thomas Braun (thomas.braun@virtuell-zuhause.de)" license="LGPL" >
+<language name="LaTeX" version="13" section="Markup" kateversion="5.0" priority="10" extensions="*.tex;*.ltx;*.dtx;*.sty;*.cls;*.bbx;*.cbx;*.lbx;*.tikz;*.pgf" mimetype="text/x-tex" casesensitive="1" author="Jeroen Wijnhout (Jeroen.Wijnhout@kdemail.net)+Holger Danielsson (holger.danielsson@versanet.de)+Michel Ludwig (michel.ludwig@kdemail.net)+Thomas Braun (thomas.braun@virtuell-zuhause.de)" license="LGPL" >
   <highlighting>
     <!-- NOTE: Keywords of kind "\something" do not need a delimiter before "\".
          Using a DetectChar rule with lookAhead to detect "\" at the beginning
@@ -437,7 +437,7 @@
 
       <context name="LabelOption" attribute="Normal Text" lineEndContext="#stay">
         <DetectSpaces/>
-        <DetectChar char="(" attribute="Math" context="MathModeTex" />
+        <Detect2Chars char="\" char1="(" attribute="Math" context="MathModeLatex"/>
         <DetectChar char="\" attribute="Macro" context="ContrSeq"/>
         <DetectChar char="$" attribute="Math" context="MathModeTex" />
         <DetectChar char="%" attribute="Comment" context="Comment"/>
@@ -461,7 +461,7 @@
 
       <context name="FancyLabelParameter" attribute="Environment" lineEndContext="#stay">
         <DetectSpaces/>
-        <DetectChar char="(" attribute="Math" context="MathModeTex" />
+        <Detect2Chars char="\" char1="(" attribute="Math" context="MathModeLatex"/>
         <DetectChar char="\" attribute="Macro" context="ContrSeq"/>
         <DetectChar char="$" attribute="Math" context="MathModeTex" />
         <DetectChar char="%" attribute="Comment" context="Comment"/>
@@ -492,7 +492,7 @@
 
       <context name="SpecialCommandParameterOption" attribute="Option Text" lineEndContext="#stay">
         <DetectSpaces/>
-        <Detect2Chars char="\" char1="(" attribute="Math" context="MathModeTex" />
+        <Detect2Chars char="\" char1="(" attribute="Math" context="MathModeLatex" />
         <DetectChar char="\" attribute="Macro" context="ContrSeq"/>
         <DetectChar char="$" attribute="Math" context="MathModeTex" />
         <DetectChar char="%" attribute="Comment" context="Comment"/>