The world of medicinal chemistry is vast. Thousands of drugs exist, each designed to interact with the human body in a specific way. To study them systematically, scientists classify drugs into broad categories based on their mechanism of action and therapeutic purpose.
Drugs are broadly classified into two major categories:
| Category | What It Does |
|---|---|
| Pharmacodynamic Agents | These drugs do NOT kill bacteria or viruses. Instead, they regulate and control the normal physiological functions of the body — such as reducing fever, relieving pain, inducing sleep, or numbing sensation. |
| Chemotherapeutic Agents | These drugs directly attack and destroy disease-causing organisms (pathogens) such as bacteria, viruses, fungi, or parasites. Antibiotics fall under this category. |
Think of it this way:
This chapter focuses on Pharmacodynamic agents and their five major types.
Pharmacodynamic agents are drugs that interact with the body's own physiological systems to regulate, control, or modify normal body functions. They do not target or kill any external pathogen (bacteria, virus, fungus, etc.). Instead, they work by adjusting the body's internal mechanisms.
For example:
The word "Pharmacodynamics" itself comes from two Greek roots:
So, Pharmacodynamics literally means "the study of how drugs change or influence the body's functions."
Below are the five major types of Pharmacodynamic drugs, explained in detail:
Antipyretics are drugs (medicines) that are used to lower abnormally high body temperature — that is, to reduce fever.
The word "Antipyretic" is formed from two parts:
So, Antipyretic literally means "against fever" or "fever-fighting."
The normal body temperature of a healthy human being is approximately:
This temperature is maintained by a small region in the brain called the Hypothalamus, which acts as the body's internal thermostat. When you are healthy, the hypothalamus keeps your temperature stable at 37°C.
When a pathogen (such as a bacteria or virus) enters the body, the immune system fights back. During this fight, the body releases chemicals called Prostaglandins (specifically PGE₂). These chemicals signal the hypothalamus to raise the body's temperature "set point" — for example, from 37°C to 39°C or even 40°C.
The body then responds by:
This results in fever — the body's temperature rises above normal. Fever is actually a defence mechanism, as higher temperatures make it harder for bacteria and viruses to survive. However, if the fever becomes too high (above 40°C or 104°F), it can become dangerous and even life-threatening, potentially causing brain damage or seizures.
Antipyretic drugs work by inhibiting the enzyme Cyclooxygenase (COX), which is responsible for the synthesis of Prostaglandins. When Prostaglandin production is blocked, the hypothalamus receives no signal to raise the temperature, and it resets the body's thermostat back to the normal 37°C.
The body then responds by:
As a result, the fever comes down.
This is a critical point for examinations. If a normal, healthy person (with no fever) takes a Paracetamol tablet, their body temperature will NOT drop below 37°C. The person will not develop hypothermia (dangerously low body temperature).
Why? Because antipyretics only work by blocking the excess Prostaglandin signal that raises the temperature above normal. If there is no excess signal (because the person is already at normal temperature), the drug has nothing to block, and the temperature remains unchanged at 37°C.
In simple terms:
| Drug | Notes |
|---|---|
| Paracetamol (Acetaminophen) | The most widely used antipyretic in the world. Sold under brand names like Crocin, Dolo, Tylenol, and Calpol. It is available over the counter (OTC) without a prescription. |
| Aminopyrine | One of the earliest synthetic antipyretics. It was widely used in the early 20th century but has been largely replaced by safer alternatives due to its potential to cause agranulocytosis (a dangerous reduction in white blood cells). |
| Aspirin (Acetylsalicylic acid) | Also acts as an antipyretic, in addition to being an analgesic and anti-inflammatory agent. However, it is not recommended for children under 16 due to the risk of Reye's Syndrome (a rare but serious condition affecting the liver and brain). |
| Ibuprofen | A non-steroidal anti-inflammatory drug (NSAID) that also has antipyretic properties. Commonly sold as Brufen. |
Imagine a child develops a fever of 102°F (38.9°C) due to a viral infection. The parents take the child to a doctor, who prescribes Paracetamol syrup (Calpol). Within 30–45 minutes of taking the medicine, the child begins to sweat, and the temperature gradually drops back to 98.6°F. The Paracetamol did not kill the virus — it simply brought the temperature down to a safe level. The child's own immune system will eventually eliminate the virus.
Anesthetics are drugs that are used to induce loss of sensation (numbness) or loss of consciousness (unconsciousness) in the body. They are essential in modern surgery, as they allow doctors to perform operations without the patient feeling any pain.
The word "Anesthetic" comes from the Greek word anaisthetos:
So, Anesthetic literally means "without sensation" or "loss of feeling."
Anesthetics are classified into two major types based on the extent of numbness they produce:
Definition: General anesthetics are drugs that render the entire body unconscious. The patient loses all awareness, all sensation, and all ability to feel pain. They are in a state of deep, controlled unconsciousness throughout the surgical procedure.
How They Work: General anesthetics act on the Central Nervous System (CNS) — specifically the brain — to depress neural activity. They interfere with the transmission of nerve signals in the brain, effectively "shutting down" consciousness while keeping vital functions (heartbeat, breathing) alive under careful medical monitoring.
Administration: General anesthetics can be administered in two ways:
Examples:
| Drug | Details |
|---|---|
| Chloroform (CHCl₃) | One of the earliest general anesthetics, used widely in the 19th century. It was administered by soaking a cloth in liquid Chloroform and placing it over the patient's nose and mouth (as seen in movies when kidnappers use it). It is no longer used today because it was found to cause severe liver damage (hepatotoxicity) and cardiac arrhythmias (irregular heartbeat). |
| Ether (Diethyl Ether, C₂H₅OC₂H₅) | Another historically important general anesthetic. It was the first substance to be publicly demonstrated as a surgical anesthetic in 1846 by Dr. William T.G. Morton at Massachusetts General Hospital — an event now known as "Ether Day." Ether is highly flammable, which made it dangerous in operating rooms, and it has been replaced by safer alternatives. |
| Cyclopropane (C₃H₆) | A gaseous anesthetic that was used in the mid-20th century. It provided rapid induction of anaesthesia but was also highly flammable and explosive, making it risky. It has been largely discontinued. |
| Halothane (CF₃CHBrCl) | A modern inhalation anesthetic that replaced Chloroform and Ether. It is non-flammable and provides smooth induction. It is still used in some developing countries. |
| Isoflurane, Sevoflurane, Desflurane | These are the most commonly used general anesthetics in modern hospitals. They are fluorinated ethers that are non-flammable, fast-acting, and allow precise control of the depth of anaesthesia. Sevoflurane is especially popular for paediatric (children's) surgery because it has a pleasant smell and does not irritate the airways. |
| Thiopental (Intravenous) | A barbiturate drug injected intravenously to rapidly induce unconsciousness before switching to an inhalation agent for maintenance. It acts within 30 seconds of injection. |
Clinical Note: The doctors who specialise in administering anaesthesia are called Anesthetists (or Anesthesiologists in some countries). This is a highly specialised field within medicine (MBBS + MD in Anaesthesia). Anesthetists must calculate the exact dosage of the drug based on the patient's body weight, age, medical history, and the expected duration of surgery. Too little anaesthesia, and the patient may wake up during surgery (a terrifying condition called "anaesthesia awareness"). Too much, and the patient may stop breathing or suffer cardiac arrest. The margin for error is extremely small.
Definition: Local anesthetics are drugs that numb only a specific, targeted area of the body without making the patient unconscious. The patient remains fully awake and alert but feels absolutely no pain in the numbed region.
How They Work: Local anesthetics work by blocking sodium ion channels (Na⁺ channels) in the nerve fibres of the targeted area. Normally, pain signals travel along nerves as electrical impulses, which depend on sodium ions entering the nerve cell through these channels. When the channels are blocked, no electrical signal can be generated, and no pain signal reaches the brain. The area becomes completely numb.
Administration: Local anesthetics are typically injected directly into the tissue near the surgical site, or applied as a cream/spray on the skin surface.
Examples:
| Drug | Details |
|---|---|
| Novocaine (Procaine) | One of the earliest local anesthetics, synthesised in 1905. It was the standard local anesthetic used by dentists for many decades. It has been largely replaced by newer agents that provide faster and longer-lasting numbness. |
| Benzocaine | A surface (topical) local anesthetic found in many over-the-counter products. It is used in throat lozenges (to numb a sore throat), in teething gels for babies (to numb sore gums), and in sunburn creams (to relieve burning pain). It is applied directly to the skin or mucous membrane. |
| Lidocaine (Lignocaine) | The most widely used local anesthetic in modern medicine. It is used by dentists (injected into the gums before a tooth extraction), by surgeons (injected around a wound before stitching), and in minor procedures like removing a skin tag or mole. It acts faster and lasts longer than Novocaine. It is also used as an anti-arrhythmic drug (to correct irregular heartbeat). |
| Bupivacaine | A long-acting local anesthetic commonly used in epidural anaesthesia (injection near the spinal cord to numb the lower body during childbirth or lower-limb surgery). |
| Tetracaine | A potent local anesthetic used for eye surgeries (applied as eye drops to numb the surface of the eye before procedures like cataract removal). |
Real-Life Scenario: Imagine you visit a dentist because of a painful cavity. The dentist says the tooth needs to be extracted. Before pulling the tooth, the dentist takes a small syringe and injects Lidocaine into your gum near the affected tooth. Within 2–3 minutes, that entire side of your mouth goes completely numb. You feel pressure and movement during the extraction, but absolutely no pain. You are fully awake, you can talk, and you can see everything — but the pain signals from that area are completely blocked. After 2–3 hours, the numbness wears off, and sensation returns to normal.
| Feature | General Anesthetic | Local Anesthetic |
|---|---|---|
| Consciousness | Patient becomes completely unconscious | Patient remains fully awake |
| Area affected | Entire body | Only a specific, targeted area |
| Pain relief | Total — patient feels nothing at all | Only in the numbed region |
| Administration | Inhaled (gas/vapour) or injected intravenously | Injected near the site or applied topically |
| Monitoring | Requires continuous monitoring by an anesthetist | Minimal monitoring required |
| Recovery time | Longer — patient needs time to regain consciousness | Shorter — numbness wears off in 1–3 hours |
| Risk level | Higher — risk of respiratory failure, cardiac complications | Lower — generally very safe |
| Used for | Major surgeries (open-heart surgery, brain surgery, organ transplants) | Minor procedures (dental work, stitching a wound, removing a mole) |
| Examples | Chloroform, Ether, Sevoflurane, Isoflurane | Lidocaine, Benzocaine, Novocaine, Bupivacaine |
Analgesics are drugs that are used to relieve severe physical or internal pain without causing loss of consciousness. Unlike anesthetics (which numb sensation entirely), analgesics specifically target the pain pathway to reduce or eliminate the sensation of pain while the patient remains awake.
The word "Analgesic" comes from the Greek word analgēsia:
So, Analgesic literally means "without pain" or "pain-relieving."
Analgesics are prescribed in situations where the patient is experiencing severe, unbearable pain that cannot be managed by simple remedies. Common scenarios include:
Analgesics work by interfering with the pain signal transmission pathway between the site of injury and the brain:
Analgesics block this pathway at one or more points:
Analgesics are broadly classified into two categories:
These are milder painkillers that work by inhibiting the COX enzyme and reducing Prostaglandin synthesis. They are used for mild to moderate pain and are generally non-addictive.
Examples: Aspirin, Ibuprofen, Paracetamol, Naproxen.
These are available over the counter and are commonly used for headaches, menstrual cramps, muscle aches, and mild joint pain.
These are powerful, strong painkillers derived from or mimicking compounds found in opium (from the poppy plant). They act directly on the opioid receptors in the brain and spinal cord to block pain perception and produce a feeling of euphoria (intense well-being).
Examples:
| Drug | Details |
|---|---|
| Morphine | The most well-known and historically important narcotic analgesic. Named after Morpheus, the Greek god of dreams. It is extracted from the latex of the opium poppy (Papaver somniferum). It is extremely effective for severe pain, especially in cancer patients and post-surgical patients. However, it is highly addictive — prolonged use leads to physical dependence and tolerance (needing higher doses for the same effect). |
| Pethidine (Meperidine) | A synthetic opioid analgesic. It was once widely used in hospitals for post-operative pain and labour pain. It is less potent than Morphine but still carries a risk of addiction. |
| Novalgin (Metamizole / Dipyrone) | A powerful analgesic and antipyretic that also has anti-inflammatory properties. It is used in some countries for severe pain, renal colic (kidney stone pain), and post-surgical pain. However, it has been banned or restricted in several countries (including the USA and UK) due to the risk of agranulocytosis (a dangerous drop in white blood cells). |
| Fentanyl | A synthetic opioid that is approximately 50 to 100 times more potent than Morphine. It is used in hospitals for extreme pain management (such as during open-heart surgery or for terminally ill cancer patients). It is administered as an injection, transdermal patch (skin patch), or lozenge. Due to its extreme potency, even a tiny overdose can be fatal — it has been involved in many accidental overdose deaths worldwide. |
| Codeine | A mild opioid found naturally in opium. It is less potent than Morphine and is commonly used in cough syrups (as a cough suppressant) and in combination with Paracetamol for moderate pain. It is less addictive than Morphine but still requires a prescription. |
| Tramadol | A synthetic opioid with moderate potency. It is commonly prescribed for moderate to moderately severe pain (such as after dental surgery or orthopaedic procedures). It has a lower addiction potential than Morphine but is still a controlled substance. |
Narcotic (opioid) analgesics are among the most effective painkillers known to medicine, but they carry a serious risk of addiction and dependence. When a person takes opioids regularly:
This is why opioid analgesics are classified as Schedule H or Schedule X drugs in India and as Controlled Substances in many countries. They can only be obtained with a valid prescription from a licensed physician, and their distribution is strictly monitored.
The global Opioid Crisis (especially in the United States) has highlighted the devastating consequences of opioid overprescription and misuse, leading to hundreds of thousands of overdose deaths.
Hypnotics are drugs that are used to induce artificial sleep in patients who are unable to fall asleep naturally. They are commonly known as sleeping pills.
The word "Hypnotic" comes from the Greek word hypnos, meaning sleep. (This is the same root from which the word "Hypnosis" is derived.)
So, Hypnotic literally means "inducing sleep."
Hypnotics are prescribed to patients suffering from insomnia — a condition characterised by the inability to fall asleep or stay asleep. Common situations where hypnotics may be prescribed include:
Hypnotics work by depressing the Central Nervous System (CNS). They enhance the activity of an inhibitory neurotransmitter called GABA (Gamma-Aminobutyric Acid) in the brain. GABA's normal function is to calm down neural activity — it acts as the brain's natural "brake pedal."
When a hypnotic drug enhances GABA's effect:
The depth and duration of sleep depend on the type and dose of the hypnotic drug.
| Drug | Details |
|---|---|
| Veronal (Barbital) | One of the very first synthetic sleeping pills, introduced in 1903 by Bayer (the German pharmaceutical company). It was a barbiturate — a class of drugs that were the standard sleeping pills for much of the 20th century. However, barbiturates have a very narrow therapeutic index, meaning the difference between an effective dose and a lethal dose is very small. Many accidental and intentional overdose deaths occurred with Veronal and other barbiturates. It is no longer in common use. |
| Luminal (Phenobarbital) | Another barbiturate hypnotic. It was used both as a sleeping pill and as an anti-epileptic drug (to prevent seizures). Like Veronal, it carries a significant risk of overdose and addiction. It is still used in some countries as an anti-epileptic but has been largely replaced as a sleeping pill. |
| Benzodiazepines | This is the class of hypnotics that is most widely preferred in modern medicine. Benzodiazepines are highly effective at inducing sleep, and — crucially — they have a much wider therapeutic index than barbiturates, meaning they are much safer in terms of overdose risk. They also have fewer side effects. Common benzodiazepine hypnotics include: |
| — Diazepam (Valium) | One of the most prescribed drugs in history. Used for anxiety, insomnia, muscle spasms, and seizures. |
| — Nitrazepam | A benzodiazepine specifically used as a sleeping pill for short-term treatment of severe insomnia. |
| — Alprazolam (Xanax) | Primarily an anti-anxiety drug, but also used for sleep induction in patients whose insomnia is caused by anxiety. |
| — Zolpidem (Ambien) | A newer non-benzodiazepine hypnotic that is very commonly prescribed today. It acts on the same GABA receptors as benzodiazepines but has a different chemical structure. It induces sleep quickly and has a short duration of action, so patients do not feel groggy the next morning ("next-day drowsiness"). |
| Chloral Hydrate | One of the oldest synthetic hypnotics, first prepared in 1832. It was famously known as "Mickey Finn" when slipped into drinks to render someone unconscious (a practice depicted in old detective novels and films). It is rarely used today due to its toxicity and potential for abuse. |
Like opioid analgesics, hypnotic drugs (especially barbiturates and benzodiazepines) carry a risk of dependence and addiction. Patients who take sleeping pills for extended periods may find that:
For this reason, modern medical guidelines recommend that hypnotics be prescribed only for short-term use (typically 2–4 weeks) and that non-pharmacological approaches (such as Cognitive Behavioural Therapy for Insomnia, sleep hygiene practices, and relaxation techniques) be tried first.
| Feature | Barbiturates (e.g., Veronal, Luminal) | Benzodiazepines (e.g., Diazepam, Nitrazepam) |
|---|---|---|
| Era of use | Early to mid-20th century | Late 20th century to present |
| Effectiveness | Highly effective | Highly effective |
| Safety (Therapeutic Index) | Very narrow — small difference between effective and lethal dose | Much wider — significantly safer |
| Overdose risk | Very high — can be fatal | Lower — rarely fatal on its own (but dangerous when combined with alcohol or opioids) |
| Addiction potential | High | Moderate to high |
| Current status | Largely discontinued as sleeping pills | Still widely prescribed, but with caution |
| Antidote in overdose | No specific antidote | Flumazenil — a specific antidote that reverses benzodiazepine effects |
Antiseptics are chemical substances that are applied to living tissues (such as skin, wounds, or mucous membranes) to prevent the growth of, or destroy, harmful microorganisms — including bacteria, viruses, and fungi.
The word "Antiseptic" comes from:
So, Antiseptic literally means "against infection" or "preventing decay."
When you get a cut, scrape, or wound on your skin, the protective barrier of the skin is broken. This creates an entry point for bacteria, viruses, and fungi from the surrounding environment. If these microorganisms enter the wound and begin to multiply, they cause infection — characterised by redness, swelling, warmth, pain, and the formation of pus (a thick, yellowish-white fluid consisting of dead white blood cells, dead bacteria, and tissue debris).
Antiseptics work by:
Because human skin is relatively thick, tough, and resilient, it can withstand the mild chemical assault of an antiseptic without being damaged. The microorganisms on the skin surface, however, are tiny and fragile, and they are quickly destroyed.
This is a commonly tested comparison in examinations:
| Feature | Antiseptics | Disinfectants |
|---|---|---|
| Applied to | Living tissues (skin, wounds, mucous membranes) | Non-living surfaces (floors, tables, surgical instruments, countertops) |
| Purpose | To kill or inhibit microorganisms on the body | To kill or inhibit microorganisms on surfaces and objects |
| Concentration | Generally lower concentration (safe for skin) | Generally higher concentration (too harsh for living tissue) |
| Effect on skin | Safe — does not damage living tissue | Can cause chemical burns or irritation if applied to skin |
| Example | Dettol (when diluted and applied to skin), Savlon, Betadine | Phenol (used to clean hospital floors), Lysol, Bleach (Sodium hypochlorite) |
The same chemical can act as an antiseptic at low concentrations and as a disinfectant at high concentrations. For example, Phenol (Carbolic acid) at a 0.2% concentration is an antiseptic (safe for skin), but at a 1% concentration, it is a disinfectant (used to clean floors and surfaces).
| Antiseptic | Details |
|---|---|
| Dettol | The most commonly recognised antiseptic in Indian households. The active ingredient in Dettol is Chloroxylenol (4-Chloro-3,5-dimethylphenol), which constitutes about 4.8% of the solution. When you pour Dettol into water for a bath or to clean a wound, it turns the water milky white (due to emulsification). Dettol is used to clean minor cuts, scrapes, and wounds, and is also added to bathing water during illness to prevent the spread of infection. |
| Savlon | Another popular antiseptic solution. Its active ingredients are Cetrimide (a quaternary ammonium compound) and Chlorhexidine. It is gentler on the skin than Dettol and is often preferred for cleaning wounds on children. |
| Betadine (Povidone-Iodine) | A widely used antiseptic in hospitals. It contains Iodine complexed with a carrier molecule (Povidone). It has a characteristic dark brown colour. It is applied to the skin before and after surgical procedures, to clean wounds, and to prepare the skin for injections. It is effective against a broad spectrum of bacteria, viruses, fungi, and spores. |
| Hydrogen Peroxide (H₂O₂) | A mild antiseptic available as a 3% solution. When poured on a wound, it fizzes and bubbles — this is because the enzyme Catalase in damaged cells breaks down H₂O₂ into water and oxygen gas. The bubbling action helps physically dislodge dirt and dead tissue from the wound. It is commonly used to clean minor cuts at home. |
| Mercurochrome (Merbromin) | An older antiseptic that contains mercury. It was applied to wounds as a bright red/pink liquid. It has been largely phased out due to concerns about mercury toxicity. |
| Boric Acid (H₃BO₃) | A mild antiseptic used as an eye wash (very dilute solution) to treat minor eye infections and as a dusting powder to prevent fungal infections. |
| Alcohol (Ethanol, 70%) | A 70% solution of ethanol is an excellent antiseptic. It is used to swab the skin before an injection or blood draw. Interestingly, 100% (absolute) alcohol is less effective as an antiseptic because it evaporates too quickly and does not penetrate bacterial cell walls effectively. The 30% water in the 70% solution helps the alcohol penetrate the cells. |
Imagine a child falls while playing in the park and scrapes their knee. The skin is broken, and dirt and bacteria from the ground have entered the wound. The mother immediately washes the wound with clean water, then applies Dettol solution (diluted with water) using a cotton ball. The Chloroxylenol in Dettol kills the bacteria on and around the wound. She then applies a bandage. The wound heals cleanly without infection — thanks to the antiseptic.
If the antiseptic had not been applied, the bacteria could have multiplied inside the wound, causing a painful infection with pus formation, redness, and swelling — potentially requiring antibiotic treatment.
| # | Type | What It Does | Word Meaning | Examples | Key Point |
|---|---|---|---|---|---|
| 1 | Antipyretics | Reduces fever (high body temperature) | Anti (against) + Pyretic (fever) | Paracetamol, Aminopyrine, Aspirin | Does NOT cause hypothermia in healthy persons |
| 2 | Anesthetics | Induces numbness or unconsciousness | An (without) + Aisthetos (sensation) | General: Chloroform, Ether, Sevoflurane; Local: Lidocaine, Benzocaine, Novocaine | General = whole body unconscious; Local = specific area numb |
| 3 | Analgesics | Relieves severe pain | An (without) + Algesis (pain) | Morphine, Pethidine, Novalgin, Fentanyl, Tramadol | Narcotic analgesics are highly addictive |
| 4 | Hypnotics | Induces artificial sleep (sleeping pills) | Hypnos (sleep) | Veronal, Luminal, Diazepam, Zolpidem | Benzodiazepines are preferred over barbiturates today |
| 5 | Antiseptics | Kills germs on living tissue (skin/wounds) | Anti (against) + Sepsis (infection) | Dettol, Savlon, Betadine, H₂O₂ | Different from Disinfectants (which are used on non-living surfaces) |
To remember all five types of Pharmacodynamic drugs effortlessly, imagine them as five different types of friends in your school or college:
This is the friend who calms you down when you are extremely angry, heated up, or "burning" with rage. Whenever your temperature is rising (you are losing your temper), this friend comes and cools you down, bringing you back to your normal, calm state — just like an antipyretic brings your body temperature back to normal 37°C.
This is the friend who takes you to a party, a gaming session, or a movie marathon to make your mind completely numb — so numb that you completely forget all your embarrassing moments, failures, fears, and worries. You lose all sensation of emotional pain. You are "unconscious" to your problems. Just like a general anesthetic makes you unconscious to physical pain.
This is the patient, empathetic friend who sits with you when you are going through deep emotional pain — a heartbreak, a family loss, or a personal failure. This friend listens to you, comforts you, and helps relieve your internal pain. They don't make you unconscious (that's the anesthetic friend) — they just help you bear and reduce the pain. Just like an analgesic relieves physical pain without causing unconsciousness.
This is the boring friend (or that one professor) whose lectures, stories, or monotonous talks are so dull and repetitive that you instantly fall asleep. You cannot keep your eyes open. Within minutes, you are in deep sleep. Just like a hypnotic drug (sleeping pill) induces artificial sleep.
This is the bodyguard friend who always keeps bad people, toxic people, and harmful influences away from you. Whenever someone tries to "infect" you with negativity, bad habits, or harmful company, this friend steps in and eliminates the threat. Just like an antiseptic kills harmful bacteria and prevents infection on your skin.
Classification of Drugs: Pharmacodynamics is a fundamental concept in organic chemistry. Understanding the mechanisms, reaction conditions, and stereo-chemical outcomes is crucial for mastering organic chemistry. Our curated resources provide step-by-step visualizations to help you excel.
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What is the main characteristic of a pharmacodynamic drug?
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Pharmacodynamic drugs act on the body's own physiological systems to regulate or modify normal functions, such as temperature, pain, sensation, sleep, or local microbial growth.
Pharmacodynamic drugs primarily regulate body functions. Chemotherapeutic drugs are designed to attack disease-causing organisms or abnormal cells.
The five types covered here are antipyretics, anesthetics, analgesics, hypnotics, and antiseptics.