Drugs, the word is not new to us. Amongst many, it creates a frightful response. So far we have heard that drugs are the substance of addiction and a reason for the spoiled generation. Yes, they are addictive but all of them are not harmful. Biologically speaking, they target our brain and switch the mood and physiological conditions of the body. However, there are legal drugs as well as illegal drugs. Here we will discuss legal drugs and classification of drugs.
By definition, drugs are chemical substances that affect or alter the physiology when taken into a living system. They can either be natural or synthetic. Chemically, they are low atomic mass and molecular mass structures. When a drug is therapeutically active and is used for the diagnosis, treatment or prevention of a disease, it is called medicine (legal drugs). They target the macromolecules inside the body and generate a biological response. Most of them interrupt the nervous system (especially brain) for the generation of a proper biological response. However, they can be toxic in higher doses called lethal dose.
Classification of Drugs
Classification of drugs can be done on the basis of different criteria. Some of the criteria for the classification of drugs are given below.
On the basis of pharmacological effect:
How a drug or medicine affects or influences the cells of an organism is referred to as the pharmacological effect. Drugs have different pharmacological effects on an organism; say, for example, an analgesic reduces the pain while an anti-inflammatory drug reduces the inflammation of the body. Thus, drugs can be classified based on the pharmacological effect.
On the basis of drug action:
Different drugs act differently i.e., each drug has its own way of generating response called drug action. Drug action is more specified according to how it generates a response. For example, there are lots of medicines to treat hypertension but each type of drug has different drug action. All the hypertension medicines reduce the blood pressure but in a different pathway.
On the basis of chemical structure:
This is a common classification of drugs. Generally, drugs which have same drug action and pharmacological effect have a basic skeletal structure and a minute variation in the branching. This is why some drugs have more potential than the other. For example, all sulphonamides have the same skeletal structure.
On the basis of molecular targets:
Drugs target the macromolecules inside the body to generate a biological response. Such macromolecules are called target molecules or drug targets. Drugs which have the same mechanism of action will have the same target. This basis for classification of drugs is more helpful during clinical trials.
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