Sjögren-Larsson syndrome is a rare hereditary metabolic disorder characterized by congenital ichthyosis, mental retardation, and spastic diplegia or tetraplegia. This genetic disease is caused by fatty acid aldehyde dehydrogenase deficiency, leading to an accumulation of long-chain alcohols. The role of enzyme in the degradation of leukotrienes paved the way to the development of a new therapeutic strategy for Sjögren-Larsson syndrome, leukotriene antagonists. We describe a 3-year-old boy with Sjögren-Larsson syndrome who had a lipid peak on proton magnetic resonance spectroscopy despite normal findings on cerebral magnetic resonance imaging. He benefited from treatment with montelukast sodium, especially with respect to the agonizing pruritus.