This document presents information about aminoglycoside antibiotics. It discusses their classification, mechanisms of action, pharmacokinetics, antibacterial spectrum, uses, and toxicity. Aminoglycosides are a class of antibiotics that work by binding to the bacterial ribosome and inhibiting protein synthesis. They are primarily used to treat infections caused by aerobic gram-negative bacteria. Their toxicity includes nephrotoxicity and ototoxicity due to accumulation in the kidney and inner ear structures. Drug interactions can also cause increased toxicity when combined with other nephrotoxic or ototoxic medications.

1. PRESNTED BY- GANESH VASUDEV MAHAJAN
M.PHARM 1ST YEAR SEM-2
DEPARTMENT –PHARMACOLOGY
RAJARSHI SHAHU COLLEGE OF PHARMACY,
BULDANA
AMINOGLYCOSIDE
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2. •FLOW OF PRESENTATION
 INTRODUCTION.
 GRAM POSITIVE AND NEGATIVE BACTERIA
 CLASSIFICATION OF AMINOGLYCOSIDES
 MECHANISM OF ACTION
 PHARMACOKINETICS
 ANTIBACTERIAL RESISTANCE
 ANTICATERIAL SPECTRUM
 USES
 AMINOGLYCOSIDESTOXICITY
 DRUG INTERACTION 2/19

3. •INTRODUCTION
 Amino glycosides are natural product or semi-
synthetic derivatives of highly water soluble
compounds produced by a variety of soil
actinomycetes.
 Streptomycin was first number discovered in 1944
by waksman and his colleagues.
 Amikacin a derivatives of kanamycin and netilmicin
,a derivatives of sisomicin,are semisynthetic
product.
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4.  Aminoglycosides ( gentamicin, tobracymycin
,amikamycin , netilmycin , kanamycin,
streptomycin , Paromomycin , and neomycin)
are used primarily to treat infections caused by
aerobic gram-negative bacteria.
 Streptomycin and amikacin are the important
agents for the treatment of mycobactrial
infections and paromomycin is used orally for
intestinal amebiasis.
 Widely in combination with a β-lactum
antibiotics
 - serious infection with gram-negative bacteria
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5.  -combination with vancomycin gram-
negative endocarditis.
 Treatment of tuberculosis
 Aminoglycosides are bacterial inhibitors of
protein synthesis.
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6. •GRAM POSITIVE&NEGATIVE BACTERIA
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7. •CLASIFIACTON OF AMINOGLYCOSIDES
 SYSTEMIC -TOPICAL
- STREPTOMYCIN -NEOMYCIN
- GENTAMYCIN -FRAMYCETIN
- KANAMYCIN
- AMIKACIN
- SISOMYCIN
- NETILMICIN
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8. •MECHANISM OF ACTION
 Aminoglycosides binds to 30s ribosomal units of bacteria
Prevents the formation of initiation complex , which is the
prerequisites for peptide synthesis
Lack of the formation of initiation complex causes the 30s sub unit
to misread the genetics code on mRNA
Incorrect amino acids thus incorporated into the growing peptide
chain which is are of no use for bacterial growth
Leads to bacterial death 8/19

9. 9/19

10. •Aminoglycosides also act...
 Formed improper initiation complex blocks the
movement of ribosome's
resulting in a mRNA attached with single
ribosome's
Thus amino glycosides also interfere in the assemble
of p0lysomes
Results in the accumulation of non functional
ribosome's
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11. •Pharmacokinetics
 ABSORPTION – amino glycosides are highly
polar so they have poor oral bioavailability
 Therefore they given parenterally (IM route )
or applied locally
 METABILOSM - these are poorly distributed
and poorly protein bound when given
parenterally they failed to reach intraocular
fluid or CSF
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12.  METABOLISM –as they do not penetrate more cellular
compartment they do not under go any significant
metabolism
 EXCRETION-
 Mainly by kidney through glomerular filtration.
Resulting in fairly high urinary concentration
so they can be used in the treatment of URINARYTRACT
INFECTIONS.
Their excretion directly proportional to creatinine
clearance
Normal half life varies from 1.5 hrs, it may increased to
24-48 hrs in patients with renal insufficiency
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13. • Anti bacterial resistance
 Synthesis of plasmid mediated bacterial transferase
enzymes ( acetyl transferases , phoshotransferases
and adenyl transferases) that can inactive
aminoglycosides by acetylation, phosphorylation
and adenylation respectively.
 By development of mutation or deletion of porin
channels.
 Alteration of receptor proteins on 30s ribosomal
units.
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14. •Anti bacterial spectrum
 Activity is primarily directed against gram negative
aerobicbacilii (Ecoli , klebsiella, shingella , )
 Only a few gram positive cocci are inhibited
(staphylococcus aureas ,streptococcus viridians and
faecalis )
 These are not effective against gram positive
BACILLI , gram negative COCCI and ANAEROBES.
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15. •Aminoglycosides uses
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16. •Aminoglycosides toxicity
 Nephrotoxicity
 Inhibition of intracellular lysosomal phospholipase A2 in renal
brush border and of free aminoglycosides into cytosol
Then this free drug blocks the calcium transport in mitochondria
by displacing calcium
Leading to mitochondria degradation and necrosis
Causes chronic renal failure
Nephrotoxicity
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17.  Ototoxicity (irreversible)
 Aminoglycosides causes impairment of 8th cranial
nerve function
 They accumulate in endolymph ( vetibular) ,
perilymph (cohlear) and causes ireeversible
damage
 Vestivbular damage is characterised by vertigo
ataxia and loss of balance where as cochlear
damage leads to hearing loss and tinnitus
 And neuromuscular blocking effect ( Ach release)
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18. •Drug interaction
 Aminoglycosides + local anaesthetics/skeletal
muscle relaxants
Leads to paralysis
 Aminoglycosides should not be given with
ototoxic and nephrotoxic drug like
tetracycline, furosemide , amphotericin B
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19. Thank you
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