There are also negative effects on the lungs that the tars and resins of marijuana can cause, particularly when it is mixed with tobacco. It has been proven that smoking marijuana can and will contribute to illnesses or disorders such as asthma and pulmonary emphysema. Although no known cases of death have been causal to smoking marijuana, it has been theorized that some types of cancer originate due to agitation of the body alone. Because marijuana users often inhale the unfiltered smoke deeply and then hold it in their lungs as long as possible, chronic marijuana use may play a role in the development of chronic respiratory problems.
Marijuana impairs skills requiring eye-hand coordination and a fast reaction time, reduces motor coordination, tracking ability and perceptual accuracy. It impairs concentration, and time appears to move more slowly, and reduces maximal exercise capacity resulting in increased fatigability. It can lead to memory and learning problems, difficulty concentrating, perception distortions involving vision, sound, touch and time, thinking and problem-solving difficulties, increased heart rate and drop in blood pressure, sudden feelings of anxiety, including panic attacks, and paranoia and a runny nose, sore throat and wheezing. Because marijuana is stored in the body fat, its effects may be long-lasting and stay with you for up to 72 hours. Additionally, long-term use has been associated with motivational problems including apathy, impaired judgment, loss of ambition and an inability to carry out long-term plans.