Chemistry Of Antidepressants

The chemistry of antidepressants
How they work with the nervous system.
Mental illness has always been a problem but it is now recently that the awareness for it has increased, with depression being one of the main illnesses. There are many medicines for treating depression that are widely used, but like so many medicines people do not actually understand what happens in the body once the drug has been taken. Through this essay I hope to explore the different types of drugs used to treat depression and how they work within the body. The symptoms of clinical depression are described as being in a state of low mood that can last for months that affects a person’s thoughts and behaviour leading to them having a lack of productivity. There are

The main classes of antidepressants that will be discussed are the monoamine oxidase inhibitors (MAOIs), Tricyclic Antidepressants (TCAs) and serotonin reuptake inhibitors (SSRIs). It usually depends on the patient’s specific needs as to what medicine would be prescribed to treat the depression. SSRIs are the most popular and widely prescribed antidepressants by doctors because of the fewer side effects, whereas TCAs are not usually recommended as first time treatment due to the less pleasant side effects. TCAs are also supposed to be more dangerous in the case of an overdose, which is another reason these older antidepressants are not recommended as often. The antidepressant drugs work by altering how the neurotransmitters move in the nervous system. The drugs work in different ways by either decreasing the breakdown of the neurotransmitters that affect mood, or some antidepressants stop the reuptake of those chemicals. The main neurotransmitters that are targeted are serotonin and norepinephrine as when they are lacking in concentration, depression is more likely to be caused. Some people can have low levels of serotonin and norepinephrine due to their genetics. However some environmental, behavioural and

Tricyclic antidepressant drugs were originally created to help treat those suffering with another mental illness known as schizophrenia, but the results were not as successful as hoped. On the other hand this research showed the first evidence that they help those with depression. Common anti-depressants in this class that are used are amitriptyline, amoxapine (Asendin), desipramine (Norpramin) and Imipramine (Tofranil), which was the first drug in this class of antidepressants to be used clinically. The TCA antidepressants work as they block the reuptake of norepinephrine and serotonin. This means that these chemicals cannot be recycled which keeps more of these chemical messengers out in the synapse which increases the probability of the message reaching the postsynaptic neuron. The synapse is the small gap between two nerve cells which allows neurotransmitters to pass through by diffusion, and the postsynaptic neuron is where these neurotransmitters attach and either excite or inhibit this neuron. The tricyclic drugs are made up of a central ring of seven or eight atoms with a side chain containing at least 2 carbon atoms, though 3 seem to be better, and the amine group can be either tertiary or secondary. Although the structure can vary slightly all TCAs function in the same way, it is their selectivity and