Use and Action of Medicines: We suffer from various kinds of diseases due to our lifestyle, unhealthy habits, and polluted environment. Medicines are used as the first aid for almost all diseases as they can cure them or atleast relieve the pain. Medical science is continuously making tremendous developments in the progress of medicines, thereby curing a long list of dangerous diseases and saving the lives of many human beings. 

There are more medicines available than diseases themselves. Some of these can be bought from pharmacies, and some are available through a doctor’s prescription only. In this article, we will learn what medicine is and its types, how it acts, and its effects on the human body.

What are Medicines?

Medicines or drugs are the natural or synthetic chemical compounds used to prevent or cure a disease, or they can also be used to relieve pain. Medicines are obtained from different sources. Some medicines are byproducts of certain microorganisms like bacteria, fungus, etc., for example, Penicillin from a fungus (Penicillium notatum). Some of these are biologically engineered by inserting genes into bacteria that make them produce the desired substance or medicine. There are fewer effective drugs against viruses than bacteria.

Most medicines are used to cure a disease or condition. For example, antibiotics are given to cure an infection. Certain medicines are also given to treat a medical condition; for example, antidepressants are given to treat depression. Another use of medicine is to relieve symptoms of an illness. For example, pain relieves to reduce pain. Lastly, vaccines are also medicines that are used to prevent diseases in advance by stimulating the immune system of the body. For example, Covishield and Covaxin are the vaccines used to prevent Covid-19.

Fig: Medicines

Study About Chemicals in Medicines Here

Classification of Medicines

Medicines are obtained from a variety of sources. Many of them are made of natural sources, while others are made in laboratories using different chemicals. Based on its source, medicines are classified into two types: Traditional medicines and modern medicines.

Traditional medicines

1. Traditional medicines are also called indigenous medicines or folk medicines.
2. Traditional medicines are developed over generations within the fold beliefs of various societies before the modern era of medicine. Ayurvedic medicines are the traditional medicines of India.
3. These types of medicines are mostly derived from plants or animals. These are not usually processed medicines.
4. Traditional medicines can cause serious side effects to some patients. For example, a medicine with a high amount of alkaloid is toxic to the liver. 

Fig: Traditional Medicines

Some of the examples of traditional medicines are given below:

Medicinal Plants	Uses
Aloe vera	To heal wounds, treat skin problems, treat dental plaque, reduce constipation and blood sugar level, etc.
Centella asiatica (Gotu Kola)	To treat depression and for longevity.
Orthosiphon aristatus (Cat’s whiskers)	To treat gout, diabetes, and rheumatism.
Ocimum basilicum (Basil)	To treat coughs, colds, and bronchitis.
Medicinal Animal	Uses
Sea cucumber	To treat Japanese encephalitis.
Centipede	To treat lockjaw and convulsions.
Ant	To treat hepatitis B.

Modern Medicines

1. Modern medicines are medicines that are made in laboratories by scientists. These medicines are based on substances found in nature. 
2. The active ingredients in modern medicines are identified, extracted, and purified. 
3. After that, the medicines are tested repeatedly in many different ways before it is marketed. It allows scientists to make sure that the medicines are safe and to identify their side effects.  

Fig: Modern Medicines

There are different types of modern medicines:

Analgesics

These are the medicines that are used to relieve pain without causing numbness or affecting consciousness. It does not treat the cause of pain but only provides relief from that pain. Some of the examples of analgesics are paracetamol, aspirin, and codeine. Antipyretics are medicinal preparation used to treat fever. The antipyretic analgesics drugs are a combination of an analgesic action with the ability to reduce body temperature during fever. Paracetamol, Ibuprofen, and Acetylsalicylic acid are the most commonly used antipyretic agents.

Antibiotic

Antibiotics are used to treat infectious diseases caused by microorganisms like bacteria and fungi. It cannot treat the infections caused by viruses such as cold and flu. Some of the examples of antibiotics are Penicillin, Tetracycline, Streptomycin, etc. Antibiotics can be broad-spectrum (ability to act on several pathogens) or narrow-spectrum (acts on only specific pathogens with a limited range of actions). Antibiotics should be used when prescribed by the doctor.

Vaccines

Vaccines are the preparation of a killed or weakened microbe extracted from the pathogen. It stimulates the immune system of the body against the microbe,  thereby preventing disease.  Vaccinations or immunisations work by stimulating the active immune system, the natural disease-fighting system of the body.

Serum

Serum is the pre-prepared antibodies from another source injected to build an immediate passive immunity. These antibodies containing serum are obtained from vaccinating animals such as horses or rabbits. When the immunity system of the animal produces antibodies against the weakened pathogen, these antibodies are separated from their blood cells by coagulation. On coagulation, the liquid left is called serum separates, which contains antibodies. It is stored and used for passive immunity. 

Though vaccine and serum action sound similar, there are some main differences. Differences between vaccines and serum are tabulated below:

Vaccine	Serum
Vaccines consist of dead or weakened pathogens that stimulate the production of antibodies in the blood.	It consists of antibodies that have been produced by some other organism.
Vaccines provide active immunity.	Serum provides passive immunity.

Antitoxins

These are a type of antibodies that are capable of interacting with the corresponding toxin and neutralising them. It can be obtained from animals, plants, or bacteria. The production of antitoxins is similar to serum production. A subject animal is injected with a safe amount of toxin. The active immune system produces antibodies (antitoxins) in response. These antitoxins are separated and injected into a human or an animal in need to induce passive immunity.

Psychotherapeutic Medicines

These medicines are used to treat patients with mental illness. These are used to alter abnormal thinking, feelings, or behaviours. They do not treat mental illness but reduce the symptoms of it. Some of the types of these medications are stimulants, antidepressants, and antipsychotics.

Routes of Administering Medicines

Medicines can get inside the bodies in several different ways. These different ways are called routes. The most common medicine route is orally (through the mouth) in the form of pills/tablets, capsules, or liquids. However, if a person cannot take medicine orally or the oral form of medicine is not available, then medicine can enter the body through different routes as follows:

1. Oral medications are taken by mouth, in pill, capsule, or liquid form; they are swallowed and pass into the digestive system.  
2. Nasal medications are absorbed through the thin mucous membrane inside of the nose.
3. Buccal (placed in the cheek) medications and sublingual (placed under the tongue) medications are absorbed in the mucous membrane inside the mouth and enter the bloodstream in this way. 
4. Transdermal (through the skin) medications are applied by creams or lotions; then, they are passed through the skin into the blood vessels. 
5. Topical medications can be applied to the skin directly. They tend to have a very localised effect and do not enter the bloodstream.
6. Subcutaneous medications are injected into the adipose tissue below the skin, and from there, the medicine is passed into the bloodstream.
7. Enteral medications are given through a G tube or a J tube which go directly into the stomach or intestine. Then it is passed into the digestive system, then through the liver and bloodstream.  
8. Rectal and vaginal medications, like suppositories, enemas, and creams, are inserted into the rectum or the vagina. Then they are absorbed by the rectal or vaginal wall blood vessels. 
9. Inhaled medications are inhaled directly, so it affects the lungs directly.

Fig: Routes of Administering Medicines

Drug Action

Medicines affect only the rate at which existing biological functions have proceeded. 

They do not change the basic nature of these biological functions or create new biological functions. For example, medicines can speed up or slow down the biochemical reactions that cause muscles to contract, glands to secrete substances (such as mucus, stomach acid, or insulin), kidney cells to regulate the volume of water and salts eliminated by the body, and nerves to transmit messages.

Medicines cannot restore the functions or structures already damaged. This limitation of drug action underlies the current frustration in treating tissue-destroying or degenerative diseases such as arthritis, Parkinson’s disease, muscular dystrophy, multiple sclerosis, and Alzheimer’s disease. 

Some drugs can help the body repair itself. For example, antibiotics can allow the body to repair damage caused by the disease or infection by stopping an infection.

Some medicines are hormones, such as insulin, estrogens, thyroid hormones, or cortisol. It can be used to replace natural hormones which are missing from the body.

Pros and Cons of Medicines

If the FDA (Food and Drugs Administration) considers a medicine safe enough to approve, it means that its benefits outweigh its known risks. The medications we use play an important role in overall health. All medicines have side effects, warnings, and drug interactions, so it’s important to understand the pros and cons of medicines.

Benefits of medicines

1. The benefits of medicines are the beneficial effects that help the body heal, ease pain, control blood sugar, lower blood pressure, and cure infections.
2. Pharmaceutical medicines work faster to cure diseases and illnesses as compared to herbal medicines. They also have the capability to prevent other diseases and decrease mortality rates. 
3. Besides pills and capsules, vaccines also help to fight disease and infection. Vaccination also helps the body to produce antibodies, and hence it strengthens immunity.

Side-effects/Adverse effects of medicines: The risks or side-effects of medicines are the possible unwanted or unexpected effects that might happen to us when we use them. Side-effects can be minor, like a mild upset stomach, or more serious, such as an increased risk of bleeding or liver damage.

1. Some of the mild adverse effects of medicines can be constipation, skin rash or dermatitis, dizziness, diarrhoea, headache, drowsiness, nausea, insomnia, etc.
2. Some of the serious effects of medicines can be abnormal heart rhythm, suicidal thoughts, cancer, internal bleeding. 
3. Medicine may also cause side effects like drug allergy, skin rash, liver inflammation, redness in the eye, throat infections, etc.  
4. One of the most common effects of medicine is pharmaceutical drug abuse, due to which a person may become addicted to certain medications. 
5. The misuse of pharmaceutical drugs may also cause the death of an individual.

Summary

Medicine or drugs are the chemicals or compounds used to prevent or cure a disease, or they can also be used to relieve pain. They are used to ease symptoms or to help in diagnosing the illness. Medicines are classified into two types-Traditional medicines (indigenous or folk medicines) and Modern medicines. There are different types of medicines (based on their preparation), such as liquid medicines, tablets, capsules, drops, inhalers, topical medicines (ointments and lotions), suppositories, injections, etc. There are various routes for the medicines to enter the body, such as oral, nasal, buccal, sublingual, transdermal, topical, etc. Medicines affect only the rate at which existing biological functions have proceeded. They do not change the basic nature of these biological functions or create new biological functions. All medicines have side effects, warnings, and drug interactions, so it’s important to understand the pros and cons of medicines.

Frequently Asked Questions (FAQs) on Use and Action of Medicines

Q.1. What are medicines? 
Ans: Medicine or drugs are the chemicals or compounds used to prevent or cure a disease, or they can also be used to relieve pain. They are used to ease symptoms or to help in diagnosing the illness.

Q.2. Give some examples of traditional medicines. 
Ans: Aloe vera (to treat skin wounds), Centella Asiatica (to treat depression and longevity), Sea cucumber (to treat Japanese encephalitis).

Q.3. What are the types of modern medicines?
Ans: There are different types of modern medicines like analgesics (pain killers), antibiotics (to treat bacterial infections), and psychotherapeutic medications (to treat mental illness). 

Q.4. What are the types of medicines based on preparation? 
Ans: There are different types of medicines (based on their preparation), such as liquid medicines, tablets, capsules, drops, inhalers, topical medication (ointments and lotions), suppositories, injections, etc. 

Q.5. What are the negative effects of medicines on health?
Ans: Mild adverse effects of medicines can be constipation, skin rash or dermatitis, dizziness, diarrhoea, headache, drowsiness, nausea, insomnia, etc. Serious effects of medicines can be abnormal heart rhythm, suicidal thoughts, cancer, internal bleeding. 

Learn About Classification Of Drugs Here

We hope this article on the Use and Action of Medicines helps you in your preparation. Do drop in your queries in the comments section if you get stuck and we will get back to you at the earliest.