Sub mrshkei()
Dim arr, arr2, arr3, i As Long, lr As Long
lr = Cells(Rows.Count, 1).End(xlUp).Row + 1
arr = Range(Cells(1, 1), Cells(lr, 1))
k = 1
For i = LBound(arr) To UBound(arr)
If arr(i, 1) <> Empty Then
    arr2 = Split(arr(i, 1), ", ")
    ReDim arr3(0 To UBound(arr2), 1 To 1)
    For n = LBound(arr2) To UBound(arr2)
        arr3(n, 1) = arr2(n)
    Next n
    Cells(k, 1).Resize(UBound(arr3) + 1, 1) = arr3
    arr3 = Empty
    k = k + n
End If
Next i
End Sub