Disclaimer: “Gas” strains are known for their strong, diesel-like aroma and high THC content; use cautiously, start with a low dose, and consume responsibly, especially if new to cannabis or sensitive to strong effects.AAAA Northern Lights Mediums By Green Valley - 21% THCTHC levels can reach 16-21%, making this one of the most potent strains available on any market. A couple hits is all it takes for most patient's seeking this strain's powerful body effects, an upbeat mix of euphoria and physical relaxation. CBD levels are less clear, but they certainly aren't high enough to recommend this as a treatment for seizures or other conditions that respond to CBD. Even so, Northern Lights is a highly useful medical strain, effective at treating anxiety, pain, and insomnia, as well as lack of appetite.