Articles by David S. Klein, MD

Pectoralis minor syndrome is an often-missed cause of shoulder, chest, and arm pain. It occurs when a tight chest muscle compresses nerves and blood vessels beneath it. Symptoms can include tingling, weakness, and discomfort that worsens with posture or overhead activity. With proper diagnosis, most patients improve using simple strategies like stretching, strengthening, and posture correction—avoiding unnecessary procedures.

N-acetyl cysteine (NAC) is emerging as a valuable adjunctive therapy for bipolar disorder, particularly for persistent depressive symptoms. By replenishing glutathione, modulating glutamate, reducing inflammation, and supporting mitochondrial function, NAC targets key biological drivers of mood instability. This article reviews the mechanisms, clinical evidence, dosing, and safety considerations for integrating NAC into bipolar care.