Lichen planus is a chronic inflammatory mucocutaneous disorder. Lichenoid drug eruption/Drug induced lichen planus is an uncommon adverse effect of several drugs. Lichen planus can be distinguished from Lichenoid drug eruption by clinical and microscopic features. Although lichenoid drug eruptions are known adverse effects of anti-tubercular therapy (ATT), idiopathic lichen planus associated with ATT is rarely reported. A 72-year-old male, diagnosed case of lumbar canal stenosis with L2-L3 tubercular spondylodiscitis was started on ATT. Five months later, he developed intensely pruritic violaceous papules all over the body with oral mucosal involvement. Based on history and clinical appearance of lesion, the diagnosis of lichen planus was made. Dermatology consultation was taken and patient was managed with corticosteroids and dapsone, with continuation of ATT. On follow up there was significant symptomatic improvement. Lichen planus should be considered in patients receiving ATT who develop characteristic skin lesions, particularly when oral mucosal involvement is present. Early recognition and dermatological evaluation are essential for appropriate management.
