Cannabis

1) Cannabis is a persistent drug which stays in the body for months at a time. This is due to THC, the main psychoactive ingredient (tetrahydrocannabinol) being fat-soluble. This means it can dissolve in the phospolipid bilayer within brain cell membranes. 10% still remains after a month, meaning a monthly smoke ensures the drug remains permanently in the brain.

2) It has a adverse effect on brain function and mood as THC affects the neurotransmitter for dopamine. The THC molecule acts as a lock into its complimentary key, producing vast quantities of dopamine. Thus inducing the 'high', which is why THC is often referred too as the 'pleasure chemical'.

3) Physical dependency can occur as THC mimics the neurotansmitter anandamide, replacing it in the brain. Thus the body no longer produces anandamide meaning if a user stops taking cannabis the receptor sites stay empty inducing anxiety, sleeplessness, irritability and even violence. Although the withdrawal symptoms are not so serve as say heroin as cannabis takes longer to dissipate from the body.

4) Psychological dependence can occur by craving for additional dopamine. This increased dopamine triggers the formation of two other substances. One damps down the effects meaning more is needed for the same effect - tolerance. The other causes new connections in the brain so the brain becomes more sensitive reminding the user of the high they felt.

5) A link has long being established that cannabis can cause or aid mental illness. A paper found that 25% of humans have a faulty gene with leads to enhanced levels of dopamine production, meaning if an adolescent uses cannabis they have a 5/6 times greater risk of developing a psychotic illness. The way it affects the body is similar to schizophrenia as sufferers have an excess of dopamine. Brain scans have clarified this further, comparing cannabis users and non-using schizophrenics.

6) It can also effect education as concentration is compromised, due to new neuron connections being hindered. It has also being attributed to lowering sperm count, underweight babies, hyperactivity in babies, reduction in white blood cell production, heart attacks and various smoking related cancers.

As you can see the list of negatives is extensive and shocking although anecdotes and some scientific papers have drawn conclusions about some medical benefits of cannabis, which are:

1) Early on, THC had been shown to be effective for some patients who suffered nausea from cancer chemotherapy treatments. Although side effects do occur and as a result it is virtually never prescribed due to more effective less harmful alternatives being available.

2) Studies have shown that cannabis can relieve muscle pain in patients suffering from multiple sclerosis, although once again side effects have being seen which include impairing posture and balance further.

3) THC has being shown to increase appetite, which although not good for most of us, when carefully managed, could aid those suffering from debilitating diseases.

Most possible uses seem to be in pain relief, although all seem to have adverse side effects. As a result little or no work to try to find uses for cannabis is being performed as most have already being exhausted.