The term 'Inside Trouble' can be summarized by the crossword solution of 'ULCER, ' which is a medical condition caused by an inflammation of the inner lining of the stomach or intestine. It is usually accompanied by abdominal pain, nausea, and vomiting. Ulcers can be caused by a variety of factors, including stress, certain medications, and bacterial infections. Treatment for ulcers typically involves medications to reduce acid production and antibiotics to treat any underlying infection.