TYB pharmacy
Pharmacology VI semester
Pharmacology notes
Tetracycline and chloramphenicol notes ppt
broad spectrum antibiotics
Third year B pharmacy pharmacology notes
Pharmacology unit 3 notes
Pharmacology VI semester notes
These are antibiotics having a macrocyclic
lactone ring with attached sugars. Erythromycin
is the first member discovered in the 1950s,
Roxithromycin, Clarithromycin and Azithromycin
are the later additions. Antimicrobial spectrum is narrow,
includes mostly gram-positive and a few gramnegative
bacteria, and overlaps considerably with
that of penicillin G. Erythromycin is highly active
against Str. pyogenes and Str. pneumoniae, N.
gonorrhoeae, Clostridia, C. diphtheriae and
Listeria, but penicillin-resistant Staphylococci
and Streptococci are now resistant to erythromycin
also.
All cocci readily develop resistance
to erythromycin, mostly by acquiring the
capacity to pump it out. Resistant Enterobacteriaceae
have been found to produce an erythromycin
esterase. Alteration in the ribosomal binding
site for erythromycin by a plasmid encoded
methylase enzyme is an important mechanism of
resistance in gram-positive bacteria. All the above
types of resistance are plasmid mediated. Change
in the 50S ribosome by chromosomal mutation
reducing macrolide binding a
Aminoglycosides(medicinal chemistry by p.ravisankar)Dr. Ravi Sankar
Aminoglycosides,Aminocyclitols,Source,Structures of streptomycin,Dihydrostreptomycin,A mention of other aminoglycoside antibiotics,Acid hydrolysis,Mechanism of action,SAR,Dihydrostreptomycin and its importance,therapeutic uses, toxicity.
INTRODUCTION
Aminoglycosides are a class of antibiotics used mainly in the treatment of aerobic gram-negative bacilli infections, although they are also effective against other bacteria including Staphylococci and Mycobacterium tuberculosis.
They are often used in combination with other antibiotics.
Streptomycin – 1944
Actinomycetes – Streptomyces griseus
Bactericidal antibiotics which is interfere with protein synthesis
Used to treat aerobic Gram –ve bacteria
Exhibit ototoxicity and nephrotoxicity
MECHANISM OF ACTION
These drugs inhibit protein synthesis in the bacteria, there permeability is increased and cell contents leak out and death of cell occurs. These drugs leave bactericidal action.
CLINICAL USES
Gram –ve bacillary infection – Septicaemia, pelvic & abdominal sepsis
Bacterial endocarditis – enterococcal, streptococcal or staphylococcal infection of heart valves
Pneumonias, Tuberculosis
Tularemia
Plague, Brucellosis
Topical – Neomycin, Framycetin:- Infections of conjunctiva or external ear and also used it before surgery.
COMMON INDICATIONS OF AMINOGLYCOSIDES
Gram negative bacillary infections particularly septicemia, meningitis, UTI’s renal, pelvic and abdominal sepsis.
Bacterial endocarditis: usually gentamicin is preferred as a part of regimen.
Other infections such as tuberculosis, plague, brucellosis etc.
Topical uses: neomycin, framycetin and sisomicin are used for various topical infections.
NURSING IMPLICATIONS
The renal function should be regularly monitored.
Patients should be regularly enquired about any side effects.
Patients should be warned for not driving or operating the machinery.
Patient should be advised to take plenty of water during the course.
Monitor the sign and symptoms of hearing loss.
These are antibiotics having a macrocyclic
lactone ring with attached sugars. Erythromycin
is the first member discovered in the 1950s,
Roxithromycin, Clarithromycin and Azithromycin
are the later additions. Antimicrobial spectrum is narrow,
includes mostly gram-positive and a few gramnegative
bacteria, and overlaps considerably with
that of penicillin G. Erythromycin is highly active
against Str. pyogenes and Str. pneumoniae, N.
gonorrhoeae, Clostridia, C. diphtheriae and
Listeria, but penicillin-resistant Staphylococci
and Streptococci are now resistant to erythromycin
also.
All cocci readily develop resistance
to erythromycin, mostly by acquiring the
capacity to pump it out. Resistant Enterobacteriaceae
have been found to produce an erythromycin
esterase. Alteration in the ribosomal binding
site for erythromycin by a plasmid encoded
methylase enzyme is an important mechanism of
resistance in gram-positive bacteria. All the above
types of resistance are plasmid mediated. Change
in the 50S ribosome by chromosomal mutation
reducing macrolide binding a
Aminoglycosides(medicinal chemistry by p.ravisankar)Dr. Ravi Sankar
Aminoglycosides,Aminocyclitols,Source,Structures of streptomycin,Dihydrostreptomycin,A mention of other aminoglycoside antibiotics,Acid hydrolysis,Mechanism of action,SAR,Dihydrostreptomycin and its importance,therapeutic uses, toxicity.
INTRODUCTION
Aminoglycosides are a class of antibiotics used mainly in the treatment of aerobic gram-negative bacilli infections, although they are also effective against other bacteria including Staphylococci and Mycobacterium tuberculosis.
They are often used in combination with other antibiotics.
Streptomycin – 1944
Actinomycetes – Streptomyces griseus
Bactericidal antibiotics which is interfere with protein synthesis
Used to treat aerobic Gram –ve bacteria
Exhibit ototoxicity and nephrotoxicity
MECHANISM OF ACTION
These drugs inhibit protein synthesis in the bacteria, there permeability is increased and cell contents leak out and death of cell occurs. These drugs leave bactericidal action.
CLINICAL USES
Gram –ve bacillary infection – Septicaemia, pelvic & abdominal sepsis
Bacterial endocarditis – enterococcal, streptococcal or staphylococcal infection of heart valves
Pneumonias, Tuberculosis
Tularemia
Plague, Brucellosis
Topical – Neomycin, Framycetin:- Infections of conjunctiva or external ear and also used it before surgery.
COMMON INDICATIONS OF AMINOGLYCOSIDES
Gram negative bacillary infections particularly septicemia, meningitis, UTI’s renal, pelvic and abdominal sepsis.
Bacterial endocarditis: usually gentamicin is preferred as a part of regimen.
Other infections such as tuberculosis, plague, brucellosis etc.
Topical uses: neomycin, framycetin and sisomicin are used for various topical infections.
NURSING IMPLICATIONS
The renal function should be regularly monitored.
Patients should be regularly enquired about any side effects.
Patients should be warned for not driving or operating the machinery.
Patient should be advised to take plenty of water during the course.
Monitor the sign and symptoms of hearing loss.
this will give brief about the peptic ulcer and give information about the drug used for peptic ulcer and classification of drugs including drugs and there use adverse effect.
These are a class of antibiotics having a nucleus of four cyclic rings. The tetracyclines are primarily bacteriostatic; inhibit protein synthesis by binding to 30S ribosomes in susceptible organism.
Subsequent to such binding, attachment
of aminoacyl-t-RNA to the acceptor (A) site of
mRNA-ribosome complex. The carrier involved
in active transport of tetracyclines is absent in
the host cells. Moreover, protein synthesizing
apparatus of host cells is less susceptible to
tetracyclines. These two factors are responsible
for the selective toxicity of tetracyclines for
the microbes.
Tetracyclines are Octahydro napthacene derivatives which are bacteriostatic potent broad spectrum antibiotics and are the most widely prescribed form of antibiotic after penicillins.
TETRA means = four
CYCL means = hydrocarbon rings
INE means = derivation.
Tetracyclines are introduced 50 years ago as potent broad spectrum antibiotics.
They are biosynthesized form acetic acid and propionic acid units in microorganisms.
Broad spectrum antibiotics chloramphenicol, anaerobic,soil bacteria. Description includes Physicochemical Properties,Mechanism of action-50S ribosome ,Inhibits Bacterial protein synthesis,Resistance,Interactions,Indications of chloramphenicol-Pyogenic meningitis.
Anaerobic infections.
Intraocular infections.
Enteric fever
Drug of choice in some conditions.
Urinary tract infections
Topically In conjunctivitis & external ear Infections. Snehal chakorkar
this will give brief about the peptic ulcer and give information about the drug used for peptic ulcer and classification of drugs including drugs and there use adverse effect.
These are a class of antibiotics having a nucleus of four cyclic rings. The tetracyclines are primarily bacteriostatic; inhibit protein synthesis by binding to 30S ribosomes in susceptible organism.
Subsequent to such binding, attachment
of aminoacyl-t-RNA to the acceptor (A) site of
mRNA-ribosome complex. The carrier involved
in active transport of tetracyclines is absent in
the host cells. Moreover, protein synthesizing
apparatus of host cells is less susceptible to
tetracyclines. These two factors are responsible
for the selective toxicity of tetracyclines for
the microbes.
Tetracyclines are Octahydro napthacene derivatives which are bacteriostatic potent broad spectrum antibiotics and are the most widely prescribed form of antibiotic after penicillins.
TETRA means = four
CYCL means = hydrocarbon rings
INE means = derivation.
Tetracyclines are introduced 50 years ago as potent broad spectrum antibiotics.
They are biosynthesized form acetic acid and propionic acid units in microorganisms.
Broad spectrum antibiotics chloramphenicol, anaerobic,soil bacteria. Description includes Physicochemical Properties,Mechanism of action-50S ribosome ,Inhibits Bacterial protein synthesis,Resistance,Interactions,Indications of chloramphenicol-Pyogenic meningitis.
Anaerobic infections.
Intraocular infections.
Enteric fever
Drug of choice in some conditions.
Urinary tract infections
Topically In conjunctivitis & external ear Infections. Snehal chakorkar
Tetracyclines, Macrolides, Chloramphenicol and Clindamycin Antibiotics for P...SourajyotiGoswami
**Four Powerhouses Against Bacteria:**
These antibiotics are warriors against a wide range of bacteria (broad-spectrum) but work in unique ways:
* **Tetracyclines (e.g., Doxycycline):** These classics inhibit protein synthesis by binding to a bacterial ribosome subunit, halting growth. They're known for being inexpensive and effective against many common infections.
* **Macrolides (e.g., Azithromycin):** Another broad-spectrum group, macrolides also block protein synthesis but at a different ribosomal site. They're popular for respiratory infections and offer convenient dosing options like single-dose packs.
* **Chloramphenicol:** This powerful broad-spectrum antibiotic disrupts protein synthesis too. However, due to rare but serious side effects, it's reserved for severe infections where other options fail.
* **Clindamycin:** This lincomycin antibiotic works differently, inhibiting protein chain elongation. It's useful against some bacteria resistant to other antibiotics and for treating serious infections like bone infections.
**Remember:**
* These are just highlights. Each drug has its own specifics regarding spectrum, strengths, and side effects.
* Always consult a healthcare professional for diagnosis and antibiotic selection.
Broad Spectrum Antibiotic:Tetracycline,four cyclic rings,Physicochemical Properties,Classification-According to source and Based on Duration of action ,Mechanism of action-30S ribosomes ,Inhibit protein synthesis,Antimicrobial spectrum
Resistance
Adverse effects
Precautions,Uses by snehal chakorkar
Leprosy
Tuberculosis
TYB pharmacy
Pharmacology semester VI notes
Pharmacology VI semester
Pharmacology notes
Third year B pharmacy pharmacology notes
Pharmacology unit 3 notes
Pharmacology VI semester notes
Beta-Lactam Antibiotics Penicillins and cephalosporins.pptxsapnabohra2
TYB pharmacy
Pharmacology VI semester
Pharmacology notes
Beta-Lactam Antibiotics Penicillins and cephalosporins
antibiotics
Third year B pharmacy pharmacology notes
Pharmacology unit 3 notes
Penicillins and cephalosporins
Pharmacology VI semester notes
beta lactam antibiotics
TYB pharmacy
Pharmacology VI semester
Pharmacology notes
Antimicrobial drugs -general considerations
antibiotics general considerations
Third year B pharmacy pharmacology notes
Pharmacology unit 3 notes
Pharmacology VI semester notes
These simplified slides by Dr. Sidra Arshad present an overview of the non-respiratory functions of the respiratory tract.
Learning objectives:
1. Enlist the non-respiratory functions of the respiratory tract
2. Briefly explain how these functions are carried out
3. Discuss the significance of dead space
4. Differentiate between minute ventilation and alveolar ventilation
5. Describe the cough and sneeze reflexes
Study Resources:
1. Chapter 39, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 34, Ganong’s Review of Medical Physiology, 26th edition
3. Chapter 17, Human Physiology by Lauralee Sherwood, 9th edition
4. Non-respiratory functions of the lungs https://academic.oup.com/bjaed/article/13/3/98/278874
NVBDCP.pptx Nation vector borne disease control programSapna Thakur
NVBDCP was launched in 2003-2004 . Vector-Borne Disease: Disease that results from an infection transmitted to humans and other animals by blood-feeding arthropods, such as mosquitoes, ticks, and fleas. Examples of vector-borne diseases include Dengue fever, West Nile Virus, Lyme disease, and malaria.
Title: Sense of Smell
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the primary categories of smells and the concept of odor blindness.
Explain the structure and location of the olfactory membrane and mucosa, including the types and roles of cells involved in olfaction.
Describe the pathway and mechanisms of olfactory signal transmission from the olfactory receptors to the brain.
Illustrate the biochemical cascade triggered by odorant binding to olfactory receptors, including the role of G-proteins and second messengers in generating an action potential.
Identify different types of olfactory disorders such as anosmia, hyposmia, hyperosmia, and dysosmia, including their potential causes.
Key Topics:
Olfactory Genes:
3% of the human genome accounts for olfactory genes.
400 genes for odorant receptors.
Olfactory Membrane:
Located in the superior part of the nasal cavity.
Medially: Folds downward along the superior septum.
Laterally: Folds over the superior turbinate and upper surface of the middle turbinate.
Total surface area: 5-10 square centimeters.
Olfactory Mucosa:
Olfactory Cells: Bipolar nerve cells derived from the CNS (100 million), with 4-25 olfactory cilia per cell.
Sustentacular Cells: Produce mucus and maintain ionic and molecular environment.
Basal Cells: Replace worn-out olfactory cells with an average lifespan of 1-2 months.
Bowman’s Gland: Secretes mucus.
Stimulation of Olfactory Cells:
Odorant dissolves in mucus and attaches to receptors on olfactory cilia.
Involves a cascade effect through G-proteins and second messengers, leading to depolarization and action potential generation in the olfactory nerve.
Quality of a Good Odorant:
Small (3-20 Carbon atoms), volatile, water-soluble, and lipid-soluble.
Facilitated by odorant-binding proteins in mucus.
Membrane Potential and Action Potential:
Resting membrane potential: -55mV.
Action potential frequency in the olfactory nerve increases with odorant strength.
Adaptation Towards the Sense of Smell:
Rapid adaptation within the first second, with further slow adaptation.
Psychological adaptation greater than receptor adaptation, involving feedback inhibition from the central nervous system.
Primary Sensations of Smell:
Camphoraceous, Musky, Floral, Pepperminty, Ethereal, Pungent, Putrid.
Odor Detection Threshold:
Examples: Hydrogen sulfide (0.0005 ppm), Methyl-mercaptan (0.002 ppm).
Some toxic substances are odorless at lethal concentrations.
Characteristics of Smell:
Odor blindness for single substances due to lack of appropriate receptor protein.
Behavioral and emotional influences of smell.
Transmission of Olfactory Signals:
From olfactory cells to glomeruli in the olfactory bulb, involving lateral inhibition.
Primitive, less old, and new olfactory systems with different path
- Video recording of this lecture in English language: https://youtu.be/lK81BzxMqdo
- Video recording of this lecture in Arabic language: https://youtu.be/Ve4P0COk9OI
- Link to download the book free: https://nephrotube.blogspot.com/p/nephrotube-nephrology-books.html
- Link to NephroTube website: www.NephroTube.com
- Link to NephroTube social media accounts: https://nephrotube.blogspot.com/p/join-nephrotube-on-social-media.html
New Drug Discovery and Development .....NEHA GUPTA
The "New Drug Discovery and Development" process involves the identification, design, testing, and manufacturing of novel pharmaceutical compounds with the aim of introducing new and improved treatments for various medical conditions. This comprehensive endeavor encompasses various stages, including target identification, preclinical studies, clinical trials, regulatory approval, and post-market surveillance. It involves multidisciplinary collaboration among scientists, researchers, clinicians, regulatory experts, and pharmaceutical companies to bring innovative therapies to market and address unmet medical needs.
Title: Sense of Taste
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the structure and function of taste buds.
Describe the relationship between the taste threshold and taste index of common substances.
Explain the chemical basis and signal transduction of taste perception for each type of primary taste sensation.
Recognize different abnormalities of taste perception and their causes.
Key Topics:
Significance of Taste Sensation:
Differentiation between pleasant and harmful food
Influence on behavior
Selection of food based on metabolic needs
Receptors of Taste:
Taste buds on the tongue
Influence of sense of smell, texture of food, and pain stimulation (e.g., by pepper)
Primary and Secondary Taste Sensations:
Primary taste sensations: Sweet, Sour, Salty, Bitter, Umami
Chemical basis and signal transduction mechanisms for each taste
Taste Threshold and Index:
Taste threshold values for Sweet (sucrose), Salty (NaCl), Sour (HCl), and Bitter (Quinine)
Taste index relationship: Inversely proportional to taste threshold
Taste Blindness:
Inability to taste certain substances, particularly thiourea compounds
Example: Phenylthiocarbamide
Structure and Function of Taste Buds:
Composition: Epithelial cells, Sustentacular/Supporting cells, Taste cells, Basal cells
Features: Taste pores, Taste hairs/microvilli, and Taste nerve fibers
Location of Taste Buds:
Found in papillae of the tongue (Fungiform, Circumvallate, Foliate)
Also present on the palate, tonsillar pillars, epiglottis, and proximal esophagus
Mechanism of Taste Stimulation:
Interaction of taste substances with receptors on microvilli
Signal transduction pathways for Umami, Sweet, Bitter, Sour, and Salty tastes
Taste Sensitivity and Adaptation:
Decrease in sensitivity with age
Rapid adaptation of taste sensation
Role of Saliva in Taste:
Dissolution of tastants to reach receptors
Washing away the stimulus
Taste Preferences and Aversions:
Mechanisms behind taste preference and aversion
Influence of receptors and neural pathways
Impact of Sensory Nerve Damage:
Degeneration of taste buds if the sensory nerve fiber is cut
Abnormalities of Taste Detection:
Conditions: Ageusia, Hypogeusia, Dysgeusia (parageusia)
Causes: Nerve damage, neurological disorders, infections, poor oral hygiene, adverse drug effects, deficiencies, aging, tobacco use, altered neurotransmitter levels
Neurotransmitters and Taste Threshold:
Effects of serotonin (5-HT) and norepinephrine (NE) on taste sensitivity
Supertasters:
25% of the population with heightened sensitivity to taste, especially bitterness
Increased number of fungiform papillae
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These lecture slides, by Dr Sidra Arshad, offer a quick overview of physiological basis of a normal electrocardiogram.
Learning objectives:
1. Define an electrocardiogram (ECG) and electrocardiography
2. Describe how dipoles generated by the heart produce the waveforms of the ECG
3. Describe the components of a normal electrocardiogram of a typical bipolar leads (limb II)
4. Differentiate between intervals and segments
5. Enlist some common indications for obtaining an ECG
Study Resources:
1. Chapter 11, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 9, Human Physiology - From Cells to Systems, Lauralee Sherwood, 9th edition
3. Chapter 29, Ganong’s Review of Medical Physiology, 26th edition
4. Electrocardiogram, StatPearls - https://www.ncbi.nlm.nih.gov/books/NBK549803/
5. ECG in Medical Practice by ABM Abdullah, 4th edition
6. ECG Basics, http://www.nataliescasebook.com/tag/e-c-g-basics
ARTIFICIAL INTELLIGENCE IN HEALTHCARE.pdfAnujkumaranit
Artificial intelligence (AI) refers to the simulation of human intelligence processes by machines, especially computer systems. It encompasses tasks such as learning, reasoning, problem-solving, perception, and language understanding. AI technologies are revolutionizing various fields, from healthcare to finance, by enabling machines to perform tasks that typically require human intelligence.
Pulmonary Thromboembolism - etilogy, types, medical- Surgical and nursing man...VarunMahajani
Disruption of blood supply to lung alveoli due to blockage of one or more pulmonary blood vessels is called as Pulmonary thromboembolism. In this presentation we will discuss its causes, types and its management in depth.
2. TETRACYCLINES
• The first to be introduced was chlortetracycline in 1948 under the
name aureomycin (because of the golden yellow colour of S.
aureofaciens colonies producing it) .
• These are a class of antibiotics having a nucleus of four cyclic rings,
obtained from soil actinomycetes.
• Being active orally and affecting a wide range of microorganisms—
called ‘broadspectrum antibiotic’
4. • The bacterial ribosome consists of 50s and 30s subunits and
tetracyclines bind to 30 s subunit.The t RNA carries amino
acids to ribosome for protein synthesis.The ribosome has 3
binding sites:viz, A, P and E sites.
• Tetracyclines bind to A site and prevent binding of tRNA to this
site.
7. Protein synthesis
• The messenger RNA (mRNA) attaches to the 30S ribosome. The
initiation complex of mRNA starts protein synthesis and polysome
formation.
• The nacent peptide chain is attached to the peptidyl (P) site of the
50S ribosome.
• The next amino acid (a) is transported to the acceptor (A) site of the
ribosome by its specific tRNA which is complementary to the base
sequence of the next mRNA codon (C).
• The nascent peptide chain is transferred to the newly attached
amino acid by peptide bond formation.
• The elongated peptide chain is shifted back from the ‘A’ to the ‘P’
site and the ribosome moves along the mRNA to expose the next
codon for amino acid attachment.
• Finally the process is terminated by the termination complex and
the protein is released
8. (1) Aminoglycosides bind to several sites at 30S and 50S subunits
as well as to their interface—freeze initiation, interfere with
polysome formation and cause misreading of mRNA code.
(2) Tetracyclines bind to 30S ribosome and inhibit aminoacyl
tRNA attachment to the ‘A’ site.
(3) Chloramphenicol binds to 50S subunit—interferes with
peptide bond formation and transfer of peptide chain from ‘P’
site.
(4) Erythromycin and clindamycin also bind to 50S ribosome and
hinder translocation of the elongated peptide chain back from ‘A’
site to ‘P’ site and the ribosome does not move along the mRNA
to expose the next codon. Peptide synthesis may be prematurely
terminated.
9. Mechanism of action
• The bacterial ribosome consists of 50s and 30s subunits and
tetracyclines bind to 30 s subunit. The t RNA carries amino
acids to ribosome for protein synthesis.
• The ribosome has 3 binding sites:viz, A, P and E sites.
• The tetracyclines are primarily bacteriostatic; inhibit protein
synthesis by binding to 30S ribosomes in susceptible organism.
• In gram-negative bacteria tetracyclines diffuse through porin
channels
• Subsequent to such binding, attachment of aminoacyl-t-RNA
to the acceptor (A) site of mRNA-ribosome complex is
inhibited.
• As a result, the peptide chain fails to grow.
10. Antimicrobial spectrum
1. Cocci: Strep. pyogenes, Staph. aureus (including MRSA) and
enterococci respond. Tetracyclines (especially minocycline) are
now active against relatively few N. gonorrhoeae and N.
meningitidis.
2. Most gram-positive bacilli, e.g. Clostridia and other anaerobes,
Listeria, Corynebacteria, Propionibacterium acnes, B. anthracis
are inhibited
3. Sensitive gram-negative bacilli are— H. ducreyi,
Calymmatobacterium granulomatis, V. cholerae,
All rickettsiae (typhus, etc.) and chlamydiae are highly sensitive.
11. Resistance
• Resistance to tetracyclines develops slowly in a graded
manner.
• In such bacteria, usually the tetracycline concentrating
mechanism becomes less efficient or the bacteria acquire
capacity to pump it out.
• Another mechanism is plasmid mediated synthesis of a
‘protection’ protein which protects the ribosomal binding site
from tetracycline.
12. Administration
• Oral capsule is the dosage form in which tetracyclines are
most commonly administered.
• The capsule should be taken ½ hr before or 2 hr after food.
Liquid oral preparations for pediatric use are banned in India.
• Tetracyclines are not recommended by i.m. route as it is
painful and absorption is poor
14. Adverse effects
Irritative effects Tetracyclines have irritant property; can cause
epigastric pain, nausea, vomiting and diarrhoea on oral ingestion.
1. Liver damage: Fatty infiltration of liver and jaundice occurs
occasionally. Tetracyclines are risky in pregnant women; can
precipitate acute hepatic necrosis which may be fatal.
2. Kidney damage: All tetracyclines, except doxycycline,
accumulate and enhance renal failure. A reversible Fanconi
syndrome like condition is produced by outdated tetracyclines.
caused by degraded products—epitetracycline,
anhydrotetracycline and epianhydrotetracycline which damage
proximal tubules.
15. 3. Phototoxicity: A sunburn-like or other severe skin reaction on
exposed parts
4. Teeth and bones: Tetracyclines have chelating property.
Calcium-tetracycline chelate gets deposited in developing teeth
and bone. Given from midpregnancy to 5 months of extrauterine
life, the deciduous teeth are affected: brown discolouration, ill-
formed teeth which are more susceptible to caries.
Tetracyclines given between 3 months and 6 years of age affect
the crown of permanent anterior dentition. Given during late
pregnancy or childhood, tetracyclines can cause temporary
suppression of bone growth.
16. 5. Antianabolic effect: Tetracyclines reduce protein synthesis and
have catabolic effect. They induce negative nitrogen balance and
can increase blood urea.
6. Diabetes insipidus: Demeclocycline antagonizes ADH action
and reduces urine concentrating ability of the kidney
7. Vestibular toxicity: Minocycline can cause ataxia, vertigo and
nystagmus,
8.Superinfection Tetracyclines are frequently responsible for
superinfections, because they cause more marked suppression of
the resident flora.
17. Precautions
1. Tetracyclines should not be used during pregnancy, lactation
and in children.
2. They should be avoided in patients on diuretics: blood urea
may rise in such patients.
3. They should be used cautiously in renal or hepatic
insufficiency.
4. Preparations should never be used beyond their expiry date.
Not to be given with milk and milk products, iron preparations,
zinc supplements, and antacids.
18. Uses
Tetracyclines are the first choice drugs:
(a)Venereal diseases: • Chlamydial nonspecific urethritis/endocervicitis: •
Lymphogranuloma venereum:
(b) Atypical pneumonia: due to Mycoplasma pneumoniae
(c) Cholera: Tetracyclines have adjuvant value by reducing stool volume and
limiting the duration of diarrhoea
(d) Brucellosis:Doxycycline200mg+rifampicin600mg for 6 weeks is DOC
e) Plague: Tetracyclines are highly effective in both bubonic and pneumonic
plague
(f) Relapsing fever: due to Borrelia recurrentis responds adequately.
(g) Rickettsial infections: typhus, rocky mountain spotted fever, Q fever,respond to
tetracyclines
Other : Doxycycline is used in COVID-19 along with other drugs.
(h)Protozoal infections:
Amoebiasis: Tetracyclines are useful in chronic intestinal amoebiasis.
Malaria:Doxycycline is given with quinine in multi drug resistant malaria
19. CHLORAMPHENICOL
• Chloramphenicol was initially obtained from Streptomyces
venezuelae in 1947.
• The commercial preparation is synthetic.
• The nitrobenzene moiety of chloramphenicol is probably
responsible for the antibacterial activity
20. Mechanism of action
• Chloramphenicol inhibits bacterial protein synthesis by
interfering with ‘transfer’ of the elongated peptide chain to
the newly attached aminoacyl-tRNA at the ribosome-mRNA
complex.
• It specifically attaches to the 50S ribosome near the acceptor
(A) site and prevents peptide bond formation between the
newly attached amino acid and the nascent peptide chain
21. Antimicrobial spectrum
• Chloramphenicol is primarily bacteriostatic, it has cidal effect
on some bacteria, e.g. H. influenzae and N. meningitidis.
(a) Chloramphenicol was highly active against Salmonella
including S. typhi,
(b) It is more active than tetracyclines against H. influenzae
(c) It is less active against gram-positive cocci, spirochetes, certain
Enterobacteriaceae and Chlamydia
22. Indications of chloramphenicol
1.Pyogenic meningitis: Chloramphenicol in a dose of 50–75 mg/kg/day
may be used as a second line drug for H. influenzae and meningococcal
meningitis, especially in young children and cephalosporin allergic
patients,
2. Anaerobic infections caused by Bact. fragilis and others (wound
infections, intraabdominal infections, pelvic abscess, and brain abscess,
etc.) respond well to chloramphenicol
3. Intraocular infections: It is the preferred drug for endophthalmitis
caused by sensitive bacteria
4. Enteric fever: The dose is 0.5 g 6 hourly (children 50 mg/kg/day) till
fever subsides, then 0.25 g 6 hourly for another 5–7 days,
5. As second choice drug (a) to tetracyclines for brucellosis and
rickettsial infections, especially in young children and pregnant women
in whom tetracyclines are contraindicated. (b) to erythromycin for
whooping cough.
6. Topically In conjunctivitis, external ear infections—chloramphenicol
0.5–5.0% is highly effective
23. ADR
• Allergy: skin rashes, angioneurotic edema, exfoliative
dermatitis
• Bone marrow toxicity: Aplastic anemia reported
• Grey baby syndrome: New born babies given Chloramphenicol
may show grey baby syndrome with manifestations as (within
2-9 days after first dose) vomiting, lethargy, anorexia, and
irregular respiration. Then hypothermia, vascular collapse,
grey cyanosis, shock .As newborn cant metabolize excrete
Chloramphenicol adequately, toxicity appears.(due to a low
level of hepatic glucuronyl transferase)
• CNS toxicity: headache, peripheral neuritis, mental confusion,
depression and delirium
24. Precautions
• Clinical use of chloramphenicol for systemic infections is now
highly restricted due to fear of fatal toxicity. Because of risk of
serious (though rare) bone marrow aplasia:
(a) Never use chloramphenicol for minor infections or those of
undefined etiology.
(b) Do not use chloramphenicol for infections treatable by other
safer antimicrobials.
(c) Avoid repeated courses.
(e) Regular blood counts (especially reticulocyte count) may
detect dose-related bone marrow toxicity