Antiseptic : Classification, Drugs, Uses

Introduction

Antiseptic is an antimicrobial substance which is applied to living tissue/skin to reduce the possibility of infection, sepsis, or putrefaction. They are generally distinguished from antibiotics by the latter ability to safely destroy bacteria within the body, and from disinfectants, which destroy microorganisms found on non-living objects.

Some antiseptics are true germicides, capable of destroying microbes (bactericidal), while others are bacteriostatic and only prevent or inhibit their growth.

A good antiseptic/disinfectant should be:

(i) Chemically stable.

(ii) Cheap

(iii) Nonstaining with agreeable colour and odour.

(iv) Cidal and not merely static, destroying spores as well.

(v) Active against all pathogens—bacteria, fungi, viruses, protozoa.

(vi) Require brief time of exposure.

(vii) Able to spread through organic films and enter folds and crevices.

(viii) Active even in the presence of blood, pus, exudates and excreta.

Relation with dis infectant

The terms ‘Antiseptic‘ and ‘disinfectant‘ tells us about an agent which inhibits or kills microbes on contact.

Conventionally, agents used on living surfaces (skin, mouth) are called antiseptics while those used for inanimate objects (instruments, privies, water supply) are called disinfectants.

Specific Antiseptic Uses=

• Hand washing

Medical professionals use antiseptics for hand scrubs and rubs in hospitals.

• Disinfecting mucous membranes.

Antiseptics can be applied to the urethra, bladder, or vagina to clean the area before inserting a catheter.

They can also help to treat an infection in these areas.

• Cleaning skin before an operation.

Antiseptics are applied to the skin before any kind of surgery to protect against any harmful microorganisms that might be on the skin.

• Treating skin infections.

You can buy OTC antiseptics to reduce the risk of infection in minor cuts, burns, and wounds. Examples include hydrogen peroxide and rubbing alcohol.

Classification

1. Phenol derivatives: Phenol, Cresol, Hexylresorcinol, Chloroxylenol, Hexachlorophene.
2. Oxidizing agents: Pot. permanganate, hydrogen peroxide, Benzoyl peroxide.
3. Halogens. Iodine, iodophor, Chlorine, Chlorophores.
4. Biguanide: Chlorhexidine.
5. Quaternary ammonium (Cationic): Cetrimide, Benzalkonium chloride, Dequalinium chloride.
6. Soaps: of Sod. and Pot.
7. Alcohols: Ethanol, Isopropanol.
8. Aldehydes: Formaldehyde, Glutaraldehyde.
9. Acids: Boric acid, Acetic acid,
10. Metallic salts: Silver nitrate, Silver sulfadiazine, Mild silver protein, Zinc sulfate, Calamine, Zinc oxide.
11. Dyes: Gentian violet, Acriflavine, Proflavine.

Drugs in detail :-

Phenol derivatives

Phenolic compounds used as antiseptics or disinfectants include pure phenol and substitution products with halogens and alkyl groups.

They act to denature and coagulate proteins and are general protoplasmic poisons.

Phenol (carbolic acid) is one of the oldest antiseptic agents.

• Cresols (also hydroxytoluene) are organic compounds which are methylphenol. They are a widely occurring natural and manufactured group of aromatic organic compounds, which are categorized as phenols (sometimes called phenolics).

Depending on the temperature, cresols can be solid or liquid because they have melting points not far from room temperature.

• Hexylresorcinol is an organic compound with local anaesthetic, antiseptic, and anthelmintic properties.

It is available for use topically on small skin infections, or as an ingredient in throat lozenges. … (in a 0.1% solution) for oral pain relief and as an antiseptic.

• Chloroxylenol also known as para-chloro meta-xylenol (PCMX), is an antiseptic and disinfectant which is used for skin disinfection and cleaning surgical instruments. It is also used within a number of household disinfectants and wound cleaners.

• Hexachlorophene, also known as Nabac, is an organochlorine compound that was once widely used as a disinfectant. The compound occurs as a white odourless solid.

In medicine, hexachlorophene is useful as a topical anti-infective, anti-bacterial agent, often used in soaps and toothpaste. It is also used in agriculture as a soil fungicide, plant bactericide, and acaricide.

Oxidizing Disinfectants

Oxidizing agents act by oxidizing the cell membrane of microorganisms, which results in a loss of structure and leads to cell lysis and death.

A large number of disinfectants operate in this way. Chlorine and oxygen are strong oxidizers, so their compounds figure heavily here.

• Potassium permanganate is a mild antiseptic with astringent properties. It is used in dermatology to treat weeping skin conditions.

• Hydrogen peroxide has been used as an antiseptic since the 1920s because it kills bacteria cells by destroying their cell walls. This process is called oxidation because the compound’s oxygen atoms are incredibly reactive, and they attract, or steal, electrons.

• Benzoyl peroxide is used to treat acne.

It works as an antiseptic to reduce the number of germs (bacteria) on the surface of your skin. It comes as a gel or face wash containing 5% benzoyl peroxide.

Halogens

Including chlorine, fluorine, and iodine, are also commonly used for disinfection. Chlorine compounds, including sodium hypochlorite, chloramines, and chlorine dioxide, are commonly used for water disinfection.

Iodine, in both tincture and iodophor forms, is an effective antiseptic.

• Povidone-iodine (PVP-I), also known as iodopovidone, is an antiseptic used for skin disinfection before and after surgery. It may be used both to disinfect the hands of healthcare providers . It may also be used for minor wounds. It may be applied to the skin as a liquid or a powder.

• iodine solution is primarily used as skin antiseptics. An iodophor is a combination of iodine and a solubilizing agent (e.g., polyvinylpyrrolidone in povidone iodine), which serves to provide a sustained-release form of iodine.

Biguanides

• Chlorhexidine is the most popular antiseptic of this group. It has potent antimicrobial activity against most gram-positive and some gram negative bacteria but not against spores.

Quaternary Ammonium or cationic

Antiseptics and Disinfectants.

The quaternary ammonium compounds are a family of antimicrobial compounds considered as potent in its disinfectant activity cationic actives, since they are active to eliminate gram positive and gram negative bacteria, although the latter to a lesser extent.

• Cetrimide is an antiseptic which is a mixture of different quaternary ammonium salts including cetrimonium bromide (CTAB). It is used as a 1-3% solution for cleaning roadside accident wounds.

• Benzalkonium Chloride is primarily used as a preservative and antimicrobial agent, and secondarily used as a surfactant. It works by killing microorganisms and inhibiting their future growth, and for this reason frequently appears as an ingredient in antibacterial hand wipes, antiseptic creams and anti-itch ointments.

• Dequalinium chloride is the active ingredient of several medications:

Dequadin an antiseptic and disinfectant. It is a topical bacteriostat. It is used in wound dressings and mouth infections and may also have antifungal action. It may cause skin ulceration.

Alcohols

Used in various forms, are used within medicine as an antiseptic, disinfectant, and antidote.

Types of alcohol used include ethanol, denatured ethanol, 1-propanol, and isopropyl alcohol.

Alcohols are effective against a range of microorganisms, though they do not inactivate spores.

• Ethanol is used in medical wipes and most commonly in antibacterial hand sanitizer gel as an antiseptic for its bactericidal and anti-fungal effects.

Ethanol kills microorganisms by dissolving their membrane lipid bilayer and denaturing their proteins, and is effective against most bacteria and fungi and viruses.

• Isopropyl alcohol is mixed with water for use as a rubbing-alcohol antiseptic. It is also used in aftershave lotions, hand lotions, and other cosmetics. In industry it is used as an inexpensive solvent for cosmetics, drugs, shellacs, and gums, as well as for denaturing ethanol (ethyl alcohol).

Aldehydes

Have a broad spectrum of activity against bacteria, fungi, and viruses. The aldehydes used are highly toxic and a long contract time is required to kill microorganisms.

• Formaldehyde a aqueous solution of formaldehyde can be useful as a disinfectant as it kills most bacteria and fungi (including their spores). It is used to kill produced vaccines.

Acid

• Acetic acid has been commonly used in medicine for more than 6000 years for the disinfection of wounds and especially as an antiseptic agent in the treatment and prophylaxis of the plague.

• Boric acid can be used as an antiseptic for minor burns or cuts and is sometimes used in salves and dressing, such as boric lint. Boric acid is applied in a very dilute solution as an eye wash.

Dyes

• Crystal violet or gentian violet (also known as methyl violet) is a triarylmethane dye used as a histological stain and in Gram’s method of classifying bacteria. Crystal violet has antibacterial, antifungal, and anthelmintic properties and was formerly important as a topical antiseptic.

• Acriflavine dye obtained from coal tar, introduced as an antiseptic in 1912 by the German medical-research worker Paul Ehrlich and used extensively in World War I to kill the parasites that cause sleeping sickness.