How do medicines work

There are many ways a drug can produce an effect, but it first needs to latch onto the target receptor. Drugs can also surreptitiously bind to other receptors, leading to unwanted side effects. This is more likely to happen if the dose is too high. In contrast, if the dose is too low, the drug fails to bind the good, target receptor and is not effective. This explains why the dose is so important when a medication is being administered.

After drugs finish their work, they leave the target receptor and wash out of the body. They may go back into blood, get transported to the liver or kidney, and get chemically changed and excreted in stool or urine. During this step, side effects can occur when a drug has an effect at a site other than its target. For a pain reliever, the target organ might be a sore muscle in the leg; irritation of the stomach could be a side effect.

Drugs destined for the central nervous system face a nearly impenetrable barricade called the blood-brain barrier that protects the brain from potentially dangerous substances such as poisons or viruses.

Fortunately, pharmacologists have devised various ways to sneak some drugs past the blood-brain barrier. Other factors that can influence distribution include protein and fat molecules in the blood that can put drug molecules out of commission by latching onto them.

How does a random group of molecules form a thinking, breathing human? How are thoughts measured? What are thoughts made of? What is the impact of follow-through in golf? Why do our bodies make boogers? Why do we sweat more in high humidity? The Royal College of Psychiatrists produces a range of easy-to-read information about different mental health conditions and the available support and treatments. Information is written by doctors in collaboration with patients and carers.

Some of the information describes how different types of mental health medicines work. The mental health charity MIND also provides helpful advice about mental health conditions and treatments including descriptions of different types of medication.

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