LCM of two numbers

This code shows how to find the LCM of two numbers.

Private Sub LCM()
        Dim intFirst, intSecond As Integer
        Dim intFirst1, intSecond1 As Integer
        Dim strOutput As String

        intFirst = 200
        intSecond = 500
        strOutput = "LCM of " & intFirst & " AND " & intSecond & " is "

        If intFirst = 0 or intSecond = 0 Then
            'If any of the two is 0 then lcm is 0.
            MessageBox.Show("LCM=0")
            Exit Sub
        Else
            'Add the numbers in the given sequence as below till
            'both numbers are equal.Variables ending with 1 are
            'used for saving the value temporarily.
            intFirst1 = intFirst
            intSecond1 = intSecond
            While intFirst <> intSecond
                If (intFirst < intSecond) Then
                    intFirst = intFirst + intFirst1
                Else
                    intSecond = intSecond + intSecond1
                End If
            End While
        End If
        MessageBox.Show(strOutput & intFirst)
    End Sub