Harlequin is sativa-dominant but very high in CBD with less than 10% THC, so there is less brain fog and euphoria while the CBD works on pain issues. Harlequin is considered by many to be the most effective for arthritis pain and also good for fibromyalgia and nerve pain, muscle and joint pain, menstrual cramps and nausea. For that study, funded via a $3 million grant from the National Center for Complementary and Integrative Health (NCCIH), the researchers hope to recruit 300 subjects to use cannabis for low back pain and observe how different combinations of THC find out here and CBD impact pain, inflammation, cognition, mood and other factors. About 50 million Americans -- fully 20% of the population -- suffer from some level of chronic pain. Thatrsquo;s more than the combined total of everyone with cancer, diabetes, and heart disease. Itrsquo;s little surprise, then, that use of painkillers can become its own issue, particularly when chronic pain can no longer be suppressed with consumer-strength medications. Long-term use of stronger drugs frequently leads to drug resistance, requiring larger doses to maintain pain reduction, or addiction, frequently an issue with opioid medications.