Magna ns symptom is seen in poisoning with:

A. CocaineCocaine Habit/ Chronic Cocaine PoisoningParikh 7th/669; Reddy 34th/561Magnate's symptom or cocaine bugs is characteristic.In this there is feeling as if grains of sand are lying under the skin or some small insects are creeping on the skin giving rise to itching sensation (formication, tactile hallucination) with resultant excoriation, leading to irregular scratches and ulcers.