Triglycerides are a form of fat (or lipid) found in the blood and which provide the body with energy. However, high triglyceride levels are linked to an increased risk of heart disease and may also be a sign of a metabolic condition. 

High triglyceride levels are usually caused by an underlying condition, such as obesity, an underactive thyroid (hypothyroidism), kidney disease, or poorly controlled diabetes. Certain medication may also raise triglyceride levels, including some steroids, beta-blockers, diuretics, and birth control pills. 

High triglyceride levels do not usually cause symptoms unless it is caused by a genetic condition, in which case fatty deposits may appear under the skin. 

Treatment of high triglyceride levels involves lifestyle changes, such as losing weight, maintaining a healthy weight, dietary changes, increasing physical exercise levels, quitting smoking and limiting alcohol intake. Medication may also be prescribed. Drug classes commonly used to lower triglyceride levels are HMG-CoA reductase inhibitors/statins, fibric acid derivatives/fibrates, omega-3 dyslipidemic agents, and niacin/vitamin B3 supplements.