An elderly patient with progressive dementia presented with nonspecific symptoms of fatigue, skin discoloration, shortness of breath, and altered mental status. She quickly developed respiratory failure requiring emergent endotracheal intubation. Initial laboratory results revealed methemoglobinemia levels greater than 30% with blood appearing black in hue. The etiology of her acute symptoms and the inciting substance of the disease was an ongoing discussion with the patient's family, which ultimately revealed accidental ingestion of lava lamp fluid as the cause. Although rare, methemoglobinemia is a medical emergency requiring prompt diagnosis and treatment. When a thorough history fails to reveal a possible source, alternative origins should be investigated, such as household products.