Jelly beans could cause a tongue of many colors, including green and black. Mouthwash can cause a colored tongue. Antibiotics can cause black tongue. Peptobismol or kaopectate can cause black tongue.
Its also depends on chocolate color.
If you detect a foul odor emanating from your mouth, and your tongue is in severe pain, then you could have an infection. If a part has turned black then you have suffered a blood clot and part of the tongue has suffered necrosis (dead tissue).
If so, make an appointment with your General Practitioner and request a consult with EENT.
Did you have a stud put through your tongue? That could cause infection or blood clots.
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