Contraindicated in Patients with Atrioventricular block, Porphyria, Anamnesis of a bone marrow depression. This medication may make you more sensitive to the sun. Limit your time in the sun. Avoid tanning booths and sunlamps. This drug may pose risks to your pregnancy, therefore please do not take this medicine without consulting your doctor first. This medication passes into breast milk. Consult your doctor before breast-feeding.