Classification of drugs

1. Anaesthetics: - An anaesthetic is a drug that causes loss of sensation. Anaesthetics are classified into 3 General Anaesthetics, Local Anaesthetics & Preoperative Anaesthetics.

1.1. General Anaesthetics: - These are drugs that aid loss of consciousness that is reversible. Examples: Diazepam, Halothane, Ketamine, Nitrous oxide, Thiopental.

1.2. Local Anaesthetics: - These are drugs that aid loss of consciousness that is reversible. Examples: Bupivacaine, Lidocaine.

1.3. Preoperative Anaesthetics: - These are drugs that are administered to make a patient unconsciousness prior to operations. Examples: Atropine, Chloral Hydrate, Diazepam, Morphine, Promethazine.

2. Analgesics, Antipyretics, Non-Steroidal Anti-Inflammatory drugs & drugs used to treat gout: - These are drugs that reduce pain, inflammation & swelling. These are classified into 2 Non-opioids & Opioid analgesics.

2.1 Non-Opioids: - These are drugs that have an anti-inflammatory effect acting peripherally. Examples: Acetylsalicylic acid, Allopurinol, Colchicines, Ibuprofen, Indometacin, Paracetamol.

2.2. Opioid analgesics: - These are drugs that act on CNS; they can be addictive, can cause sedation & have an anti-inflammatory effect. As these are habit forming, they come in the category of controlled drugs. Examples: Codeine, Morphine, Pethidine.

3. Antiallergics & drugs used in anaphylaxis: - These are drugs that prevent & relieve allergies. Examples: Chlorphenamine, Dexamethasone, Epinephrine, Hydrocortisone, Prednisolone.

4. Antidotes & anti-poisonings: - These are drugs that counteract the effects of poison. Examples: Ipecacuanha, Medicinal Charcoal, Atropine, Deferoxamine, Dimercaprol, Methionine, Methylthioninium chloride, Naloxone, Penicillamine, Potassium ferric, sodium calcium edentate, sodium nitrite, sodium thiosulfate.

5. Antiepileptics: - These are drugs that try & prevent rapid, repetitive, stimulation of the brain that causes seizure activity such as in epilepsy. Carbamazepine, Diazepam, Ethosuximide, Phenobarbital, Phenytoin, valproic acid.

6. Anti-infective drugs: - These drugs are used in the treatment of infection. These are classified as Anthelminthics, Antifilarials, Antischistosomals, Antibacterials, Antileprosy, Antituberculosis, Antifungal, Antiprotozoal, Antileishmaniasis, Antimalarial, Antitrypanosomal, Insect repellent.

6.1 Anthelminthics: - These are drugs that expel parasitic worms (helminths) & other internal parasites from the body by either stunning or killing them. Examples: Levamisole, Mebendazole, Niclosamide, Piperazine, Praziquantel, Pyrantel, Tiabendazole, Albendazole.

6.1.2. Antifilarials: - These are drugs used to destroy filaria (a worm). Esamples: Diethylcarbamazine, Ivermectin, Suramin Sodium.

6.1.3. Antischistosomals: - These are drugs that destroy or inhibit the development & reproduction of schistosomes.  Examples: Metrifonate, Oxamniquine, Praziquantel.

6.2. Antibacterials: - These are drugs that are used to destroy bacteria. Examples: Amoxicillin, Ampicillin, Benzathine Benzylpenicillin, Benzylpenicillin, Cloxacillin, Phenoxymethylpenicillin, Piperacillin, Procaine benzylpenicillin, Chloramphenicol, Erythromycin, Gentamicin, Metronidazole, Spectinomycin, Sulfadimidine, Sulfamethoxazole + Trimethoprim, Tetracycline, Ciprofloxacin, Clindamycin, Doxycycline, Nitrofurantoin, Trimethoprim.

6.2.3. Antileprosy: - These are drugs used for the treatment of leprosy. Examples: Clofazimine, Dapsone, Rifampicin.

6.2.4. Antituberculosis: - These are drugs used for the treatment of tuberculosis. Examples: Ethambutol, Isoniazid, Pyrazinamide, Rifampicin, Rifampicin + Isoniazid, Streptomycin, Hioacetazone + Isoniazid.

6.3. Antifungal: - These are drugs that destroy fungi. Examples: Amphotericin, Griseofulvin, Ketoconazole, Nystatin, Flucytosine.

6.4. Antiprotozoal: - These are drugs that destroy protozoa.

6.4.1. Antiamoebic & antigiardiasis: - Examples: Diloxanide, Metronidazole, Chloroquine.

6.4.2. Antileishmaniasis: - Examples: Meglumine Antimoniate, Pentamidine.

6.4.3. Antimalarial: - These are drugs used for the treatment of malaria.

For curative: - Examples: Chloroquine, Primaquine, Quinine, Mefloquine, Sulfadoxine + Pyrimethamine, Tetracycline.

For prophylaxis: - Examples: Chloroquine, proguanil, mefloquine.

6.4.4. Antitrypanosomal: - There are 2 types of Antitrypanosomal drugs African & American.

a. African trypanosomiasis: - Melarsoprol, Pentamidine, Suramin Sodium, Eflornithine.

b. American trypanosomiasis: - Benznidazole, Nifurtimox.

6.5. Insect repellent: - These are topical solutions that repel insects when applied on body. Examples: Diethyltoluamide.

7. Antimigraine: - These are drugs used in the treatment of migraine (a type of headache)

For treatment of acute attack: - Examples: Acetylsalicylic acid, Ergotamine, Paracetamol.

For prophylaxis: - Examples: Propranolol.

8. Antineoplastic & immunosuppressant drugs & drugs used in palliative care: - Antineoplastic are drugs that inhibit or prevent the growth & spread of neoplasms or malignant cells. These are classified into 2 Immunosuppressants & Cytotoxic drugs.

8.1. Immunosuppressant: - These are drugs that suppress immunity. Examples: Azathioprine, Ciclosporin.

8.2. Cytotoxic: - These are drugs that have toxic effects on certain cells. Examples: Bleomycin, Cisplatin, Cyclophosphamide, Cytarabine, Dacarbazine, Dactinomycin, Doxorubicin, Etoposide, Fluorouracil, Mercaptopurine, Methotrexate, Procarbazine, Vinblastine, Vincristine, Calcium Folinate.

8.3. Hormones & antihormones: - Hormones are preparations that acts like a hormone. Antihormones are preparations that blocks the action or inhibits the production of a hormone. Examples: Dexamethasone, Ethinylestradiol, Prednisolone, Tamoxifen.

9. Antiparkinson: - These are drugs that tend to relieve Parkinson disease. Parkinson is a chronic progressive neurological disease chiefly of later life that is linked to decreased dopamine production in the substantia nigra & is marked especially by tremor of resting muscles, rigidity, slowness of movement, impaired balance, & a shuffling gait—called also paralysis agitans, parkinsonian syndrome, parkinsonism, Parkinson's, Parkinson's syndrome. Examples: Biperiden, Levodopa + Carbidopa.

10.1. Antianaemic: - These are drugs effective in or relating to the prevention or correction of anemia. Examples: Ferrous salt, Ferrous salt + Folic acid, Folic acid, Hydroxocobalamin, Iron Dextran.

10.2. Drugs affecting coagulation: - These are drug/drugs that hinders coagulation & especially coagulation of the blood in short known as blood thinners. Examples: Desmopressin, Heparin, Phytomenadione, Protamine Sulfate, Warfarin.

11. Plasma substitutes: - These are artificially made substance designed to have 1 or more of the vast amount of functions of the contents of the blood. Examples: Dextran, Polygeline, Albumin.

12. Cardiovascular: - These are drugs relating to the structure & function of the heart & blood vessels. These are classified into Antianginal, Antidysrhythmic, Antihypertensive, Cardiac Glycosides, Drugs used in vascular shock, Antithrombotic.

12.1. Antianginal: - These are drugs used or tending to prevent or relieve angina pectoris. Examples: Glyceryl Trinitrate, Isosorbide Dinitrate, Nifedipine, Propranolol, Atenolol.

12.2. Antidysrhythmic: - These drugs prevent or alleviate irregularities in the force or rhythm of the heart. Examples: Lidocaine, Propranolol, Verapamil, Atenolol, Procainamide, Quinidine.

12.3. Antihypertensive: - These drugs reduce blood pressure. Examples: Hydralazine, Hydrochlorothiazide, Nifedipine, Propranolol, Atenolol, Captopril, Methyldopa, Reserpine, Sodium Nitroprusside.

12.4. Cardiac Glycosides: - These are several glycosides obtained chiefly from plant sources such as the foxglove, used medicinally to increase the force of contraction of heart muscle & to regulate heartbeats. Examples: Digoxin, Digitoxin.

12.5. Drugs used in vascular shock: - The vascular system is the body's network of blood vessels. It includes the arteries, capillaries & veins that carry blood to and from the heart. These drugs are used during inadequate tissue perfusion. Examples: Dobutamine, Dopamine.

12.6. Antithrombotic: - These drugs prevent the formation of blood clot. Examples: Acetylsalicylic acid, Streptokinase.

13. Dermatological: - These are drugs used to treat dermatological disorders. These are classified as Antifungal, Anti-infective, Anti-Inflammatory & antipruritic, Astringent, Keratoplastic and keratolytic agents, Scabicides & pediculicides & Ultraviolet-blocking agents.

13.1. Antifungal: - These drugs destroy or inhibit the growth of fungi. Examples: Benzoic acid + Salicylic acid, Miconazole, Nystatin, Sodium Thiosulfate, Selenium Sulfide.

13.2. Anti-infective: - These drugs counteract infection. Examples: Methylrosanilinium chloride, Mupirocin, Neomycin + Bacitracin, Silver Sulfadiazine.

13.3. Anti-inflammatory & antipruritic: - These are agents that reduce inflammation & relieve itching. Examples: TheBetamethasone, Calamine lotion, Hydrocortisone.

13.4. Astringent: - These are solutions that have the property of causing contraction of soft organic tissues. Examples: Aluminium diacetate.

13.5. Keratoplastic and keratolytic agents: - Keratoplastic agents promote the production of keratin. Keratolytic agents are agents that break down the outer layer of skin (keratins). Examples: Benzoyl Peroxide, Coal Tar, Dithranol, Fluorouracil, Podophyllum Resin, Salicylic Acid.

13.6. Scabicides & pediculicides: - Scabicides are drugs that destroy the itch mite causing scabies. Pediculicides are agents used to destroy lies. Examples: Benzyl Benzoate, Permethrin.

13.7. Ultraviolet-blocking agents: - These are creams that are applied to skin to protect from Sunrays. Examples: P-Aminobenzoic acid, Benzophenones, Zinc oxide.

14. Diagnostic agents: - These are agents that help in diagnosing diseases & disorders. These are classified into Ophthalmic & Radiocontrast media.

14.1. Ophthalmic: - Examples: Fluorescein, Tropicamide.

14.2. Radiocontrast media: - Examples: Amidotrizoate, Barium sulphate, Iopanoic acid, Propyliodone, Meglumine Iotroxate.

15. Antiseptics: - An antiseptic is a substance which inhibits the growth and development of microorganisms. Examples: Chlorhexidine, Hydrogen peroxide, Iodine.

16. Disinfectants: - These are agents that disinfect. Examples: Calcium Hypochlorite, Glutaral.

17. Diuretics: - These are drugs that help in eliminating water from body. Examples: Amiloride, Furosemide, Hydrochlorothiazide, Mannitol, Spironolactone.

18. Gastrointestinal: - These are drugs that treat intestinal problems. They are classified into Antacids & other antiulcer, Antiemetic, Anti-inflammatory, Antispasmodic & Cathartic drugs.

18.1. Antacids & other antiulcer: - These are agents that counteract acidity. Antiulcer are agents that heal ulcer. Examples: Aluminium Hydroxide, Cimetidine, Magnesium hydroxide.

18.2. Antiemetic: - These are drugs that alleviate nausea & prevent vomit. Examples: Metoclopramide, Promethazine.

18.3. Anti-inflammatory: - These are agents that reduce inflammation. Examples: Hydrocortisone, Sulfasalazine.

18.4. Antispasmodic: -These are agents that prevent spasm. Examples: Atropine.

18.5. Cathartic: - These are agents that assist in emptying bowels. Examples: Senna, Psyllium husks, sorbitol, magnesium citrate, magnesium sulfate, or sodium sulphate.

19. Hormones, other endocrine drugs & contraceptives: -

19.1. Adrenal hormones & synthetic substitutes: - Examples: Dexamethasone, Hydrocortisone, Prednisolone, Fludrocortisone.

19.2. Androgens: - Its male sex hormone produced by the adrenal glands & testes, the male sex glands. Example: Testosterone.

19.3. Contraceptives: -These are agents that prevent conception or impregnation. They are classified into Hormonal contraceptives, Intrauterine devices, Barrier methods.

19.3.1. Hormonal contraceptives: - Examples: Ethinylestradiol + Levonorgestrel, Ethinylestradiol + Norethisterone, Depot Medroxyprogesterone Acetate, Norethisterone, Norethisterone Enantate.

19.3.2. Intrauterine devices: - Examples: Copper-Containing device.

19.3.3. Barrier methods: - Examples: Condoms with or without spermicide (nonoxinol), diaphragms with spermicide (nonoxinol).

19.4. Estrogens: - It’s female sex hormone. Example: Ethinylestradiol.

19.5. Insulins & other antidiabetic agents: - Insulin reduces the release of glucose from the liver. Examples: Insulin injection (soluble), Intermediate-acting insulin, tolbutamide.

19.6. Ovulation inducers: - Example: Clomifene.

19.7. Progestogens: - Example: Norethisterone.

19.8. Thyroid hormones & antithyroid drugs: - These are hormones that help in the proper functioning of thyroid gland. Examples: Levothyroxine, Potassium iodide, Propylthiouracil.

20. Immunologicals: - These are agents that deal with the immune system, immunity & immune response.

20.1. Immunological Diagnostic agents: - These are agents that diagnose immunity. Examples: Tuberculin, Purified protein derivative (PPD).

20.2. Sera & immunoglobulins: - These are a group of large glycoproteins secreted by plasma cells in vertebrates that function as antibodies in the immune response by binding the specific antigens. Examples: Anti-D Immunoglobulin, Antiscorpion sera, Antitetanus immunoglobulin, Antivenom sera, Diphtheria antitoxin, Immunoglobulin, human normal, Rabies immunoglobulin.

20.3. Vaccines: - These are antigenic components used for the prevention of diseases. Examples: BCG vaccine, Diphtheria-Pertussis-Tetanus vaccine, Diphtheria-tetanus vaccine, Measles-mumps-rubella vaccine, Measles vaccine,  Poliomyelitis vaccine, Poliomyelitis vaccine, Tetanus vaccine, Hepatitis B vaccine, Influenza vaccine, Meningococcal vaccine, Rabies vaccine, Rubella vaccine, Typhoid vaccine, Yellow fever vaccine.

21. Muscle relaxants (peripherally acting) & cholinesterase inhibitors: - These are drugs that relax muscles. Examples: Chlorzoxazone, Gallamine, Neostigmine, Suxamethonium, Pyridostigmine, Vecuronium bromide.

22. Ophthalmological preparations: - These are preparations for eye. They are classified into Anti-infective agents, Anti-inflammatory agents, Local anaesthetics, Miotics & antiglaucoma drugs & Mydriatics.

22.1. Anti-infective agents: - These are agents that prevent infection in eye. Examples:  Gentamicin, Idoxuridine, Silver nitrate, Tetracycline.

22.2. Anti-inflammatory agents: - These are agents that prevent inflammation. Example: Prednisolone.

22.3. Local anaesthetics: - These are agents that cause loss of sensation to eye temporarily. Example: Tetracaine.

22.4. Miotics & antiglaucoma drugs: - Miotics are drugs that constrict the pupil & are used to treat glaucoma. Examples: Acetazolamide, Pilocarpine, Timolol.

22.5. Mydriatics: - These are drugs that dilate eye pupil. Example: Atropine

23. Oxytocics: - These are agents that promote rapid labour by stimulating contractions of the myometrium. Example: Ergometrine

24. Antioxytocics: - Example: Salbutamol

25. Psychotherapeutic drugs: - These are drugs that are prescribed for their effects in relieving symptoms of anxiety, depression, or other mental disorders. Example: Amitriptyline, Chlorpromazine, Diazepam, Fluphenazine, Haloperidol, Lithium carbonate.

26. Drugs acting on the respiratory tract: - These are classified into Antiasthmatic & Antitussives.

26.1. Antiasthmatic: - These are drugs that relieve asthma. Examples: Aminophylline, Beclometasone, Epinephrine, Salbutamol, Cromoglicic acid, Ephedrine.

26.2. Antitussives: - These are drugs that suppress cough. Example: Codeine.

Solutions correcting water, electrolyte & acid-base disturbances: - ORS, Potassium Chloride, Glucose, Glucose with Sodium Chloride, Potassium Chloride, Sodium Chloride, Sodium Hydrogen Carbonate, Compound solution of Sodium Lactate.

Vitamins & minerals: - Ergocalciferol, Iodine, Nicotinamide, Pyridoxine, Retinol, Riboflavin, Sodium Fluoride, Thiamine, Ascorbic acid, Calcium Gluconate.

N.B. The number of drugs for the above mentioned examples can be more.

References:

1. I. Darmansjah, M. M. Duran, A. W. EI-Borolossy, A. Kucers, V. K. Lepakhin, Li Jia-Tai, M. M. Reidenberg, L. A. Salako. "THE USE OF ESSENTIAL DRUGS, Model List of Essential Drugs, WHO Technical Report Series." WHO. November 22, 1991. http://apps.who.int/iris/bitstream/10665/39646/1/WHO_TRS_825.pdf (accessed December 31, 2014).

2. Consolidated list of products whose consumption and/or sale have been banned, withdrawn, severely restricted or not approved by governments, 4th ed. New York, United Nations, 1990.

3. WHO Expert Committee on Specifications for Pharmaceutical Preparations. Thirty-first report. Geneva, World Health Organization, 1990 (WHO Technical Report Series, No. 790), Annex 5.

4. Council for International Organizations of Medical Sciences. Proposed International guidelines for biomedical research involving human subjects. Geneva, 1982 (also contains the Declaration of Helsinki as revised by the 29th World Medical Assembly, Tokyo, 1975).