antiseptics and disinfectants

1. DR KAMAL OJAH
PGT, DEPT. OF PHARMACOLOGY

2. These are chemical substances which
inhibit the growth or kill microorganism
on living surfaces such as skin & mucous
membrane.
ANTISEPTICS

3. These are chemical substances which
inhibit the growth or kill microorganism
on inanimate objects such as instruments.
DISINFECTANTS

4. Characteristics of an ideal antiseptics/disinfectants
• Chemically stable
• Cheap
• Nonstaining
• Cidal, destroying spores as well.
• Active against all pathogens
• Require brief time of of exposure
• Active even in presence of blood, pus, exudates
and excreta.

5. An antiseptics in addition
• Rapid in action & exert sustained protection.
• Nonirritating to tissues.
• Nonabsorbale , produce min. toxicity if
absorbed.
• Nonsensitizing

6. • Earliest used , reference standard
• Protoplasmic poison
• Injures tissues & cells at high conc.
• Denauration of bacterial proteins
• To disinfect urine , faeces , pus.
PHENOL

7. • Methyl derivative of phenol
• Less damaging to tissues than phenol.
• 3-10 times more active
• Use for disinfection of utensils , excreta & for
washing hands.
CRESOL(Lysol)

8. • Phenol derivative
• Doesnot coagulate proteins
• Noncorrosive, nonirritating to skin
• Commercial 4.8% solution used for surgical
antiseptics
• Skin cream and soap 0.8%
• Mouth wash 1%
CHLOROXYLENOL(Dettol)

9. Pot. permanganate
• Purple crystals ,highly water soluble , liberates
oxygen
• Action is slow, high conc. cause burns
• Used for gargling ,irrigating cavities & wounds
• Also used to disinfect water in ponds
OXIDIZING AGENTS

10. • Liberates nascent oxygen which oxidizes
necrotic matter & bacteria.
• Helps in loosening & removing slough, ear
wax
HYDROGEN PEROXIDE

11. • Iodine
• Iodophores
• Chlorine
• chlorophores
HALOGENS

12. • Rapidly acting , broad-spectrum agent.
• Acts by iodinating and oxidizing microbial
protoplasm
• Use for cuts, degerming skin before surgery.
• High conc. cause burns.
IODINE

13. • Soluble complexes of iodine.
• Known as povidone iodine.
• Nonirritating, nontoxic,nonstaining & exerts
prolonged grmicidal action.
• Used on boils, furunculosis, burns ,ulcers ,
tinea,nonspecific vaginitis, disinfection of
endoscope.
IODOPHORES

14. • Rapidly acting potent germicide.
• 0.1-0.25 ppm kills most pathogen in 30 secs.
CHLORINE

15. Chlorinated lime(bleaching powder)
• Obtained by action of chlorine on lime
• Use to disinfect drinking water, swimming
pools
CHLOROPHORES

16. Sod. Hypochlorite :
• Powerful disinfectant used in dairies for milk
cans.
• Too irritant to be used as anticeptics except in
root canal therapy.

17. CHLORHEXIDINE
• Acts by disrupting bacterial cell membrane &
denaturation of bacterial proteins.
• Nonirritant , more active against gram+ve bacteria
• Used in surgical scrub, neonatal bath, mouth wash
& general skin anticeptics.
BIGUANIDES

18. CETRIMIDE:
• Detergent action
• Cidal to bacteria
• Act by altering permeability of cell membrane.
• Widely use as anticeptics & disinfectant for
surgical instruments.
QUATERNARY AMMONIUM
ANTICEPTICS

19. ETHANOL:
• Antiseptic ,cleansing agent at 40-90% conc.
• Acts by precipitating bacterial proteins.
• Irritant, should not be applied on mucous
membrane, ulcers, open wounds.
ALCOHOL

20. • Use for fumigation
• 37% aqueous solution is called formalin.
• Protoplasmic poison , denatures protein.
• Use for preserving dead tissues
• Use as antiseptics is restricted due to bad
odour
FORMALDEHYDE

21. • Less pungent, less irritant
• Broad spectrum activity
• 2% solution (cidex) use to disinfect surgical
instruments & endoscopes.
GLUTARALDEHYDE

22. BORIC ACIDS :
• Weak antiseptics , bacteriostatic
• Use for mouth wash , irrigation of eyes , glossitis
• Vomiting , abdominal pain , diarrhoea on systemic
absorption.
ACIDS

23. SILVER COMPOUNDS :
• Silver sulfadiazine is active against
pseudomonas infection.
• Silver nitrate is highly active against gonococci
METTALIC SALTS

24. Gentian violet :
• Active against gram +ve bacteria , fungi
• Use on chronic ulcers , bedsores , furunculosis,
ring worm.
DYES

25. ACRIFLAVINE :
• Active against gram +ve bacteria, gonococci
• Store in amber colored bottle.
• Nonirritant
• Use chronic ulcers and wounds