The Effects of Marijuana on the user depend on the THC it contains. The amount of THC present in Marijuana has increased since the 1970's and has stayed about the same since the mid 1980's. Marijuana originally averaged about 3 percent THC, while modern cultivation techniques have increased that figure by more than 8 times.

Hashish (the sticky resin from the female plant flowers) can contain more than 28 percent THC and Hash oil (a tar-like liquid distilled from hashish or Marijuana) can average 43 percent or more.

THC is the chemical present in Marijuana that makes you feel 'high'. Certain parts of the plant contain higher levels of THC. The flowers or buds have more THC than the stems or leaves. When Marijuana is smoked, THC goes quickly into the blood stream, through the lungs and into the brain, where it begins to affect how you feel. This can happen within a few minutes and can last up to five hours. THC is absorbed more slowly into the bloodstream when Marijuana is eaten, as it has to pass through the stomach and intestine taking up to one hour before any 'high' is experienced. When eaten, the effects can last up to 12 hours. THC is absorbed quickly into body fat and is then released very slowly back into the blood stream. This process can take up to one month, even for a single dose of THC to fully leave the body.

Short-term effects of Marijuana Abuse:
• Sleepiness
• Difficulty keeping track of time, impaired or reduced short-term memory
• Reduced ability to perform tasks requiring concentration and coordination
• Increased heart rate and potential cardiac dangers for those with pre-existing heart disease
• Bloodshot eyes, dry mouth, cough and sore throat
• Decreased social inhibitions, paranoia, and hallucinations
• Impaired or reduced comprehension and ability to learn
• Altered motivation and cognition, making the acquisition of new information difficult
• Paranoia and psychological dependence
• Impaired judgment and problem solving
• Difficulty forming concepts
• Difficulty speaking, listening effectively, thinking, and retaining knowledge
• Intense anxiety or panic attacks

Long-term effects of Marijuana Abuse and Marijuana Addiction:
* Increased risk of cancer
* Decreases in testosterone levels and lower sperm counts in men
* Increased testosterone levels in women and increased risk of infertility
* Diminished or extinguished sexual pleasure

Effects on Men
Marijuana abuse and Marijuana addiction affects the parts of the brain that control sex and growth hormones. In males, Marijuana abuse and Marijuana addiction can decrease testosterone levels. Occasional cases of enlarged breasts in male Marijuana abusers users are triggered by the chemical impact on the hormone system. Regular Marijuana abuse or Marijuana addiction can also lead to a decrease in sperm count, as well as increases in abnormal and immature sperm. Marijuana abuse and Marijuana addiction is a contributing factor in the rising problem of infertility in males. Young males should know the effects and potential effects of Marijuana use on sex drive and the growing process before they decide to smoke Marijuana

Effects on Women
Marijuana abuse and Marijuana addiction affects the female in the part of the brain that controls the hormones which determine the sequence in the menstrual cycle. It's been said that females who smoked or used Marijuana on a regular basis had irregular menstrual cycles, the female hormones were depressed, and the testosterone level was raised. Even though this effect may be reversible, it may take several months of no Marijuana use before the menstrual cycles become normal again.
Mothers who smoke Marijuana on a regular basis have been reported to have babies with a weak central nervous system. These babies show abnormal reactions to light and sound, exhibit tremors and startles, and have the high-pitched cry associated with drug withdrawal. Occurring at five times the rate of Fetal Alcohol Syndrome, Fetal Marijuana Syndrome is a growing concern of many doctors. Furthermore, doctors worry that children born to "pot-head" mothers will have learning disabilities, attention deficits and hormonal irregularities as they develop, even if there are no apparent signs of damage at birth. Pregnant or nursing mothers who smoke Marijuana should talk to their doctors immediately.

Effects on pregnant women
The abuse of any drug can affect a mother's health during pregnancy, a time when she should take special care of herself. Drug abuse may interfere with proper nutrition and rest, which can affect good functioning of the immune system. Some studies have found that babies born to mothers who used Marijuana during pregnancy were smaller than those born to mothers who did not use the drug. In general, smaller babies are more likely to develop health problems.
A nursing mother who uses Marijuana passes some of the THC to the baby in her breast milk. Research indicates that the use of Marijuana by a mother during the first month of breast-feeding can impair the infant's motor development (control of muscle movement). Research also shows more anger and more regressive behavior (thumb sucking, temper tantrums) in toddlers whose parents use Marijuana than among the toddlers of non-using parents.

Effects on the brain
Researchers have found that THC changes the way in which sensory information gets into and is acted on by the hippocampus. This is a component of the brain's limbic system that is crucial for learning, memory, and the integration of sensory experiences with emotions and motivations. Investigations have shown that neurons in the information processing system of the hippocampus and the activity of the nerve fibers are suppressed by THC. In addition, researchers have discovered that learned behaviors, which depend on the hippocampus, also deteriorate. Recent research findings also indicate that long-term Marijuana abuse and Marijuana addiction produces changes in the brain similar to those seen after long-term use of other major illicit drugs.

Effects on the lungs
Marijuana abuse and Marijuana addiction may cause many of the same respiratory problems that tobacco smoking does. Smokers cough and phlegm, symptoms of chronic bronchitis, and more frequent chest colds are common among Marijuana abusers. Continuing to smoke Marijuana can lead to abnormal functioning of lung tissue injured or destroyed by Marijuana smoke.
Regardless of the THC content, the amount of tar inhaled and the level of carbon monoxide absorbed by Marijuana abuse and Marijuana addiction are three to five times greater than among tobacco smokers. This may be due to the Marijuana users inhaling more deeply and holding the smoke in the lungs.

Effects on the cardiovascular system
Recent findings indicate that Marijuana abuse and Marijuana addiction when combined with cocaine use has the potential to cause severe increases in heart rate and blood pressure. In one study, experienced Marijuana and cocaine users were given Marijuana alone, cocaine alone, and then a combination of both. Each drug alone produced significant cardiovascular effects, but when combined, the effects were greater and lasted longer. The drugs were given with the subjects sitting quietly, while in normal circumstances, an individual may smoke Marijuana and inject cocaine and then do something physically stressful that may significantly increase the probability of overloading the cardiovascular system.

Effects on learning and social behavior
A recent study of Marijuana abuse and Marijuana addiction has shown that critical skills related to attention, memory, and learning are significantly impaired among college students who use Marijuana heavily. The study confirmed that the impairment existed even 24 hours after Marijuana use. The findings suggest that the greater impairment among heavy users is likely due to an alteration of brain activity produced by Marijuana

Longitudinal research on Marijuana abuse and Marijuana addiction among young people below college age, indicates those who use have lower achievement than non-users, more acceptance of deviant behavior, more delinquent behavior and aggression, greater rebelliousness, poorer relationships with parents, and more associations with delinquent and drug-using friends.

Marijuana Abuse
Not everyone who uses Marijuana ends up suffering the woes of Marijuana addiction. When a Marijuana abuser begins to seek out and take the drug compulsively, that person is said to be dependent on the drug and suffer from Marijuana addiction. In 1995, 165,000 people entering drug treatment programs reported Marijuana abuse as their primary problem. Some heavy Marijuana abusers show signs of dependence because when they do not use the drug, they develop withdrawal symptoms. Subjects in an experiment on Marijuana use, abuse and addiction, had symptoms such as restlessness, loss of appetite, insomnia, weight loss, and the shakes
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According to one study, Marijuana abuse by teenagers who have prior serious antisocial problems can quickly lead to Marijuana addiction or dependence on the drug. That study also found that, for troubled teenagers using tobacco, alcohol, and Marijuana, progression from their first use of Marijuana to Marijuana abuse and addiction was about as rapid as their progression to regular tobacco use, and more rapid than the progression to regular use of alcohol.
Reduction in motivation

Marijuana abuse and Marijuana addiction causes a lack of motivation in most users. Signs and symptoms of this include… not caring about what happens in their lives, lacking the desire to work regularly, sleepiness fatigue, lack of concern about how they look, and a desire and attitude to simply kick back and blow another reefer.
As a result of these symptoms, some users tend to perform poorly in school or at work.
Doorway to other drugs

Long-term studies of high school students and their behavioral patterns that include the use of drugs, show that very few young people use other drugs without first trying Marijuana The risk of using cocaine has been estimated to be more than 104 times greater for those who have tried Marijuana than for those who have never tried it. Although there are no definitive studies on the factors associated with the movement from Marijuana use to the use of other drugs, growing evidence shows that a combination of biological, social, and psychological factors are involved
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Marijuana abuse and Marijuana addiction affects the brain in many of the same ways that other drugs do. Researchers are examining the possibility that long-term Marijuana abuse and Marijuana addiction may create changes in the brain that make a person more at risk of becoming addicted to other drugs, such as alcohol or cocaine. While not all young people who use Marijuana go on to use other drugs, further research is needed to determine who will be at greatest risk.