Smiley Australia




Information on Medications


We have provided here a very basic write up on the processes in the brain that if disrupted are thought to be the cause of mental disorders.

There is also information on medications and how they work in general terms.

If you need information on a specific drug we have included links here to specialist sites where you can get this information.

These links are also available on our 'Helpful Links' page.

Biology 101 - The Human Brain:

The human brain is an amazing and very complex organ. In very simple terms it is made up of cells called 'neurons' which send and receive messages in the form of chemicals (called 'neurotransmitters') which basically dictate how we feel, move and act at any moment - happy, sad, etc.

There are many different neurotransmitters which contribute to this but the ones of particular focus in medicines currently available are Serotonin, Dopamine and Norepinephrine, these neurotransmitter chemicals are collectively referred to as 'Monoamines'.

These neurotransmitters are 'fired' by the 'sending neurons' across a small gap (called the synaptic gap), to receptors on the 'receiving neurons', this in turn fires an electrical impulse which carries the message on through the nerves to various parts of the body.

Not all of the chemical neurotransmitters fired end up in the receptors of the receiving neuron and even the ones that do are sometimes released back into the gap. There are three processes which can then come into play:

  1. Some find their way back to the sending neuron which has its own special receptors called 'auto receptors'. When chemical neurotransmitters enter these auto receptors this signals the sending neuron to stop releasing further neurotransmitters.

  2. The sending neuron can also 'reuptake' the chemical neurotransmitters and store them in 'vesicles' for later reuse. Vesicles are like containers inside the neuron that transport the neurotransmitters to their release point as well as later storing excess neurotransmitter that is reabsorbed by the neuron.

  3. Any further excess of neurotransmitter remaining in the synaptic gap is destroyed by naturally occuring chemicals (called Oxidases) which are located in the gap. This prevents over stimulation of the receiving neuron.

It is thought that a breakdown in one or more parts of this system of transmission and regulation is the cause of most mental disorders. For example it may cause you to have too much of a chemical or not enough, disrupting the delicate balance of the brain.

To use an analogy (of sorts) if you put petrol in your car it goes, if there's water in your fuel tank it doesn't go at all and if you add too much nitro it goes like a rocket for a very short time before it blows up...

Your car can't run without the right type of fuel and neither can your brain. It may over-rev, it may splutter along, or it may have difficulty starting!

It needs mentioning that there is still no scientific evidence of the involvement of the neurotransmitter 'Serotonin' in depression, and there is no scientific evidence of the involvement of 'Dopamine' in Schizophrenia - to this day these assumptions are based purely on theory.

Things that can interfere with your ability to metabolise medications effectively:

Cytochrome P450:

A relatively recent discovery of the involvement of P450 Cytochrome which is required to effectively metabolise many of these drugs. This in part may contribute some understanding to why these medications work for some and not for others.

Cytochrome P450 is a biological system involved in the production of enzymes. The production of these enzymes is determined by 50 different genes. As we are all different, not every person has all of the genes or enzymes available to metabolize these medications effectively.

Gastrointestinal Disease and Drug Metabolism:

Medications administered orally disolve into solution in the Gastrointestinal Tract before being absorbed across the gut wall into the bloodstream. Many factors can affect these processess including:

  • Gastric blood flow
  • Gastric emptying time
  • Gut PH
  • Bowel length
  • Timing of meals
  • Meal content
  • Lipid solubility
  • Concentration of nonionized molecules

Gastrointestinal disease can change these factors and affect the absorption and disposition of oral medications.

The gastrointestinal tract not only plays a role in absorption of medications it also contributes to metabolism of medications. One of these mechanisms is via two enzymes - alcohol dehydrogenase and CYP 3A4 which contribute to xenobiotic metabolism.

It you have cronic gastrointestinal disease or a temporary problem such as diarrhea you need to discuss your condition with your doctor.

Kidney (Renal) Disorders:

There are complex issues in this situation requiring expertise in the effects of renal insufficiency in drug pharmacokinetics and pharmacodynamics.

Pharmacokinetics = the movement of the drug throughout the body including absorption, distribution, metabolism and excretion.
Pharmacodynamics = the reactions between drugs and a living system, i.e. how the drug reacts with your body.

If you have kidney disease or a kidney infection or other temporary disorder you need to discuss this with your doctor.

There's No Room for a One-Size-Fits-All Attitude:

Medications are developed on the basis of humans having 'identical' mechanisms of neurological and biological functioning. Clearly this may not benefit those who fall outside our limited understanding of what constitutes 'normal' in the processes of brain and bodily fuctions.

The potential for differences in an individuals neuro transmitter and receptor systems of the brain are beyond doubt, whether these differences are genetic or caused by injury, disease or trauma.

For this reason alone it should be evident why medications work for some and not for others, and why you need a physician who is willing and interested in tailoring treatment to suit your exact needs.

Hopefully you now have some idea of what medications actually do and what their mechanisms are. There is a wealth of resources available on the internet for those who would like to study further.

The one basic understanding this information provides is the insight into just how unique and special we all are.

Information on Antidepressants:

Antidepressants in general work on the receptors of the brain responsible for the regulation of the chemical 'Seratonin'.

It is thought (there is still no scientific evidence of this) that an imbalance of Serotonin is involved in the onset of depression.

Newer, 'Second Generation' Antidepressants are:

SSRI's (Selective Serotonin reuptake inhibitors) block the automatic reuptake receptors of the sending neuron, this allows more serotonin to remain available in the synaptic gap.

SNRI's (Seratonin Noradrenaline reuptake inhibitors)block the automatic reuptake receptors of the sending neuron, this allows more noradrenaline and seratonin to remain available in the synaptic gap.

Older 'First Generation' Antidepressants are:

TCA's (Tricyclic and Tetracyclic Antidepressants)are the previous generation antidepressants. They are still in use today for people who cannot tolerate SSRI or SNRI antidepressants.

These drugs include Anafranil (Clomipramine), Tofranil (Imipramine), Amitriptyline (Tryptanol), Dothiepin (Prothiaden) and Doxepin (Sinequan).

Tricyclic antidepressants have a higher likelihood of causing seizure activity in patients and, because they have been in use longer, have a higher recorded incidence of side effects.

MOAI's (Monoamine Oxidase Inhibitors) block the natural oxidase from destroying any neurotransmitter chemicals in the synaptic gap, again allowing them to remain available.

Information on Antipsychotics:

Antipsychotics in general work on the receptors of the brain responsible for the regulation of the chemical 'Dopamine'.

It is thought that imbalances in Dopamine contributes to the onset of Psychosis and Schizophrenia.

'Typical' Antipsychotics (previous generation drugs) generally block the Dopamine (D2) receptors.

'Atypical' Antipsychotics (current generation drugs) affect different receptors, some have a greater affinity with the 5HT-2A receptors (Serotonin receptors), others work on different Dopamine receptors. Individual drug information will disclose specific action. Specialist drug information can be accessed from our Helpful Links page.

Information on Anticonvulsants:

Anticonvulsants in general work to raise an individuals seizure threshold. You may be prescribed anticonvulsants if you are diagnosed with epilepsy or if you are experiencing seizures as a result of the medications you are taking.

There are many different drugs used in the treatment of Epilepsy and these drugs have a number of different actions. Some of these drugs are used in the treatment of Bipolar Disorder also.

Our inclusion of Epilepsy on this site is with a view to educating people about the potential of medications to cause seizure activity and what to look for and the potential for certain types of Epilepsy to be misdiagnosed or mistaken for mental illness.

There are already a number of excellent websites specialising in the area of Epilepsy where you can find information on treatments and self help groups and support services. We have listed some of these on our 'Helpful Links' page for your convenience.

Benzodiazapines:

Benzodiazapines are a class of drugs used to treat anxiety and agitation. They are not given as a 'cure', rather they are used to reduce the impact and feeling of anxiety and agitation.

If you would like more information on Benzodiazapines we recommend you take a look at benzo.org.uk. This website has been around for many years and has grown to massive proportions. It covers every aspect of the use of benzodiazapines including side effects.

You will find a link to this website on our 'Helpful Links' page under 'Medications'.

Information on Specific Medications:

For information on specific drugs please use the link on our Helpful Links page.

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Information on Medication Side Effects

New Zealand Gov't Website with detailed information

RX List - Search Detailed Medication Info'

Alerts from the US Federal Drug Administration

Australian Therapeutic Goods Administration

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