macrolide antibodies

1. TOPIC
OVERVIEW OF MACROLIDE
ANTIBIOTICS

2. • WHAT ARE MACROLIDES?
• MECHANISM OF MACROLIDE ANTIBIOTICS
• WHICH INFECTIONS SHOULD MACROLIDES BE USED FOR?
• PERTUSSIS
• COMMUNITY -ACQUIRED PNEUMONIA
• TYPES OF MACROLIDES
• WHO CAN TAKE MACROLIDES?
• CAN YOU USE MACROLIDES WHILE PREGNANT OR BREASTFEEDING?
• ARE MACROLIDES SAFE?
• ARE MACROLIDE ANTIBIOTICS CONTROLLED SUBSTANCES?
• COMMON MACROLIDES SIDE EFFECTS

3. WHAT ARE MACROLIDES?
• are a class of drugs used to manage and treat
various bacterial infections. Azithromycin,
clarithromycin, and erythromycin are commonly
used to treat infections like pneumonia, sinusitis,
pharyngitis, and tonsillitis. They are also used in
uncomplicated skin infections and otitis media in
pediatric patients. Clarithromycin is used to treat
Helicobacter pylori infections in standard triple
therapy.

4. MECHANISM OF MACROLIDE ANTIBIOTICS
.Antibiotics, the drugs that help cure infectious diseases
caused by bacterial pathogens, have saved countless lives.
Unfortunately, the excessive use of antibacterials in the
clinic, veterinary medicine and farming has led to the
development of resistance. Searching for new drugs is
necessary to combat the spread of pathogens resistant to
the available antibiotics. It is equally critical to understand
the mechanistic basis of action of currently used antibiotics
because this could lead to rational, innovative strategies for
designing more efficient.

5. WHICH INFECTIONS SHOULD MACROLIDES BE USED
FOR?
Macrolides are effective against gram-positive
(excluding enterococci) and some gram-negative
bacteria. They are also active against Mycoplasma
pneumoniae, Treponema pallidum, Bordetella
pertussis, Chlamydia trachomatis, Chlamydophila
pneumoniae, Legionella spp., Campylobacter spp.
and Borrelia spp.1
First-line indications for macrolides

6. PERTUSSIS
Erythromycin 10 mg/kg (400 mg for adults), four times daily, for 14
days
Cases of pertussis (whooping cough) persist in New Zealand,
despite the vaccine being part of the National Immunisation
Schedule. Antibiotics are ineffective at reducing the duration or
severity of symptoms if given more than seven days after the
infection begins. However, antibiotics are still useful, if started
within three to four weeks of infection, to prevent transmission to
others. Women diagnosed with pertussis in the third trimester of
pregnancy, should be given antibiotic treatment regardless of the
time of onset of infection.

7. Prophylactic antibiotic treatment should be offered to
household contacts of a person with pertussis, if the
household includes a child who has not completed a
course of pertussis vaccination.

8. Erythromycin is considered the medicine of choice for
treatment and prophylaxis of pertussis as it is active
against the causative organism - Bordetella pertussis.
Infants aged under three months treated with
erythromycin are at increased risk of developing
pyloric stenosis. As the risk associated with pertussis
in a young infant is considerably greater,
erythromycin is still indicated, but the infant should
be monitored for complications for four weeks after
completion.

9. TABLE 1: COMMON FIRST-LINE INDICATIONS FOR
MACROLIDES
Infection First -line treatment Second-line treatment
Pertussis Erythromycin -
Community acquired pneumonia Amoxicillin alone
OR

10. • Amoxicillin + erythromycin (for atypical infections) Erythromycin,
roxithromycin, doxycycline or co-trimoxazole
• H. pylori Amoxicillin + clarithromycin + omeprazole Metronidazole +
clarithromycin + omeprazole
• Chlamydia Azithromycin Doxycycline, amoxicillin, erythromycin
• Acute non-specific urethritis Azithromycin
• Vancomycin (Doxycycline treatment)Community-acquired pneumonia:
atypical infection
• Amoxicillin 500 - 1000 mg, three times daily, for seven days + erythromycin
400 mg, four times daily (or 800 mg, twice daily), for seven days

11. COMMUNITY -ACQUIRED PNEUMONIA
Severe cases of pneumonia require hospitalisation. The first-line treatment
choice for pneumonia treated in the community is amoxicillin (to cover
Streptococcus pneumoniae). Erythromycin (or roxithromycin) should be
added to the treatment regimen when atypical infection is known to be
circulating in the community. Erythromycin and roxithromycin provide
coverage for Mycoplasma pneumoniae, Legionella spp. and Chlamydophilia
pneumoniae.
Resistance of S. pneumoniae to macrolides is a worldwide problem. In 2010,
resistance of S. pneumonia (non-invasive disease) to erythromycin in New
Zealand was 19%.5

12. TYPES OF MACROLIDES
KETOLIDES
These types of macrolide antibiotics are newer
derivatives from erythromycin but are known to be
more effective with improved pharmacokinetics. This is
in relation to them having two ribosomal binding sites.

13. They were developed to address the issue of
bacterial resistance that commonly occurs with the
use of traditional macrolides and have a broader
ability to address multiple bacteria. Ketolides have
been found to be quite effective against respiratory
tract infections, particularly for those with gram-
positive bacteria. They are bacteriostatic at low
doses and bactericidal at higher doses similar to
traditional macrolides.

14. Examples of ketolide antibiotics: Ketek Pak and Ket
WHO CAN TAKE MACROLIDES?
Macrolide antibiotics are relatively safe for men, women,
seniors, and children.
Because of cardiac concerns with their use, people with
known heart problems are considered high-risk patients.
Due to the potential QT prolongation with the use of
macrolides, monitoring of the heart on an ECG can also be
done as a precaution for these patients. However, it is
highly recommended that alternative treatments be sought
out first.

15. Seniors may also have lower hepatic functionality,
so close monitoring should always be done when
prescribing these medications to this
demographic.
CAN YOU USE MACROLIDES WHILE PREGNANT OR BREASTFEEDING?
Certain macrolides can be used during pregnancy and breastfeeding.
However, these medications must be monitored closely. Macrolides
are not commonly the first antibiotic drug option during the first
trimester and alternatives are highly encouraged. Currently,
clarithromycin is not recommended during pregnancy due to the
potential risk for spontaneous abortion and cardiovascular
abnormalities.

16. All macrolides can be used while breastfeeding;
however, there are known risks associated with their
use. Risks to the infant while breastfeeding includes
diarrhea, vomiting, and rash while taking macrolides.
More serious side effects include hypertrophic pyloric
stenosis in infants.

17. ARE MACROLIDES SAFE?
Macrolide antibiotics are considered safe to use. There is
some concern however with drug interactions with certain
medications so a thorough systematic review must be
performed by your healthcare provider. They must be made
aware of all medications and supplements you may be
taking so that there is no potential adverse interaction with
macrolide antibiotics. Some medications your healthcare
provider may be concerned with for potential drug
interactions may include warfarin, colchicine, cholesterol
medications, and benzodiazepines.

18. MACROLIDE ANTIBIOTIC RESTRICTIONS
• Do not use macrolides if you have:
• Hypersensitivity to medication
•History of cardiac disease particularly
arrhythmias and problems with the QT interval
•Liver disease
•End-stage kidney disease
• Irregularities with electrolytes

19. ARE MACROLIDE ANTIBIOTICS CONTROLLED
SUBSTANCES?
Macrolide antibiotics are not controlled
substances since they are not habit-forming
and they do not pose any risk of dependency
to the medication.

20. COMMON MACROLIDES SIDE EFFECTS
The majority of side effects associated with the antimicrobial macrolide usually
involve gastrointestinal distress. The most common adverse effects include:
• Nausea
• Vomiting
• Abdominal cramps
• Diarrhea
• Tinnitus
• Dizziness
• Reversible hearing loss
• Rash
• Fever
•

21. Here are some more serious reactions that can
occur with the use of macrolide antibiotics:
• Angioedema
• Severe allergic reaction
• Cholestatic jaundice
• Liver damage
• Infantile hypertrophic pyloric stenosis
• Stevens-Johnson syndrome
• Toxic epidermal necrolysis
• Acute generalized exanthematous pustulosis

22. • Clostridioides difficile associated diarrhea
• Superinfection
• Kidney damage
• Pancreatitis
• Seizures
• Hallucinations
• Reversible hearing loss
• Psychosis
• Hypoglycemia
• Death of muscle fibers

23. REFERENCES
Klein J. O. History of macrolide use in pediatries,
pediate infect Dis. J 1997 Apr, 16(4) : 427-31
(Pubished)
Parnham MJ, Erakovic Haberv, Giamarellos –
Bourboulis El, Pertetti G, Verleden GM, Vas R,
Azithromycin: mechanisms of action and their
relevance for clinical applications pharmacol Ther.
2014 Aug, 143 (2), 225 -45