Although some of the most obvious signs of drug abuse are behavioral, there are also a number of physical signs to watch for. However, like behavioral clues, physical signs will vary greatly depending upon the individual and the type of drug being used. Marijuana, for example, can produce an increased heartbeat, bloodshot eyes, dry mouth or throat, altered depth perception, and impaired short-term memory, while cocaine abuse often results in insomnia, headaches, nausea, weight loss, nose bleeds, dilated pupils, and anxiety. Opiates, such as morphine and heroin, are usually injected, so physical signs are likely to include rashes, vein inflammation, and scarring, but extreme lethargy and contracted pupils are also observable symptoms of opiate abuse. In some cases, drug abusers will become malnourished, and exhibit physical attributes such as sunken cheeks and a rippling appearance in the area of the rib cage. However, other drugs can increase the appetite, and the user may actually gain weight. For more information on the physical signs of drug abuse, consult a local health care professional.