Acute intermittent porphyria (AIP) and ichthyosis vulgaris both are autosomal dominant disorders with incomplete penetrance caused by the deficiency of porphobilinogen deaminase enzyme and filaggrin protein, respectively. We report a rare case of a 9-year-old boy having two genetic diseases with an unclear association. An acute attack of AIP is characterized by gastrointestinal symptoms and neuropsychiatric manifestations. Although rare in the first decade of life, the presence of reddish urine with a typical presentation such as abdominal pain, hypertension, seizure, and paresthesias lead us to the diagnosis of AIP. The precipitating factor in the present case was prolonged fasting in Ramadan.