Trade Name: MACROBID TABLET 500 mg
Generic Name:
Clarithromycin USP
What is Macrobid?
Macrobid is a macrolid antibiotic.
What is the Presentation of Macrobid?
Each film-coated tablet contains clarithromycin 500mg. Each box contains 1x4's
tablets.
Mechanism of action of Macrobid
Schematic diagram :
Which microorganisms are
susceptible to Macrobid?
Clarithromycin is effecitve against a wide range of microorganisms. Organisms
generally susceptible to clarithromycin include
|
Gram-positive aerobes |
Gram-negative aerobes |
Anaerobes |
Other microorganisms |
|
Staphylococcus aureus
Streptococcus pneumoniae Streptococcus pyogenes Streptococcus agalactiae
Streptococci (groups C,F,G) Viridans group of Streptococci Listeria
monocylogenes |
Haemophilus influenziae
Moraxella catarrhalis Bordetella pertussis Legionella pneumophilia
Campylobacter jejuni Neisseria gonorrhoeae Pasteurella multocida
Mycobacterium kansasii |
Clostridium perfrigens
Peptococcus niger Propionibacterium acnes Bacteroides melaninogenicus |
Mycobacterium chelonae
Mycobacterium
ovium complex
Mycobacterium
leprae
Chlamydia
trachomatis
|
|
|
|
|
|
What are the Indications of
Macrobid?
Clarithromycin is indicated for the treatment of follwoing infections
-
Upper Respiratory Tract
Infection (URTI) : Pharyngitis/tonsillitis due to Streptococcus pyogenes.
Acute maxillary sinusitis due to Streptococcus pneumoniae
-
Lower Respiratory Tract
Infections (LRTI) : Acute bacterial exacerbation of chronic bronchitis due
to Haemophilus influenzae, Moraxella catarrhalis, Streptococcus pneumoniae.
Purulent bronchitis, Bronchiectasis.
-
Pneumonia due to
Mycomlasma pneumoniae. Streptococcus pneumoniae, Chlamydia pneumoniae (TWAR),
Legionella pneumoniae, Community-acquired pneumonia.
-
Uncomplicated skin &
skin-structure infections due to Staphylococcus aureus, Streptococcus
pyogens, Mycobacterium chelonae chelonae.
-
Lyme disease
-
Odontological infections
-
Lepromatous leprosy due to
Mycobacterium leprae
-
Helicobacter pylori eradication
in peptic ulcer diseases.
What is the Dosage of Macrobid?
|
Infection |
Dosage (12 hourly) (mg) |
Normal duration (days) |
|
URTI |
250-500 |
10-14 |
|
Pharyngitis/Tonsillitis |
250 |
10 |
|
Acute maxillary sinusitis |
500 |
14 |
|
LRTI |
250-500 |
7-14 |
|
Uncomplicated skin & skin
structure |
250 |
7-14 |
|
H. pylori eradication |
500mg + Lansoprazole 30mg +
Amoxicillin 1 gm |
7 |
|
Lepromatous leprosy |
500mg once daily |
56 |
What is the Pharmacokinetic
profile of Macrobid?
Absorption : Clarithromycin is absorbed rapidly from the GIT after oral
administration, but its bioavailability is reduced to 50% - 55% because of rapid
first-pass metabolism. Peak serum concentration reaches approximately 2 hrs
after drug administration. Food delays drug absorption but does not alter its
extent.
T1/2 : The elimination half-lives of clarithromycin and 14-hydroxyclarithromycin
(active metabolite) are approximately 3-7 hrs and 5-9 hrs respectively.
Distribution : Clarithromycin is well distributed through the body and
achieves higher concentrations in tissues than in the blood.
Stability : Clarithromycin is 340 fold more stable in PH 1.39 than
Erythromycin.
High lighting features
Excellent pharmacokinetic profile Like
-
Extensive distribution into
lung tissue
-
Active both intracellularly &
extracellularly
-
Greater concentrations in the
tissues and fluid of respiratory tract than in plasma
-
Highly active against common
and emerging respiratory pathogens
-
Rapid penetration into
respiratory mucus with persistant drug concentration
Make it exclusive drug for
URTI & LRTI
Clarithromycin is highly active against URTI (Upper Respiratory Tract Infection)
& LRTI (Lower Respiratory Infection)
Both extracellularly &
intracellularly active
After examination of intracellular and extracellular activity of amoxicillin,
azithromycin and clarithromycin in infected cells the follwoing result was found
EXCELLENT TOLERABILITY PROFILE
OF CLARITHROMYCIN
Safety profile of this agent has been evaluated on the basis of adverse
reactions.
Adverse reactions were not
serious and were usually rapidly reversible. The incidence of adverse reactions
did not very with gender, race or age. Overall, clarithromycin appears to be
safe and well-tolerated macrolid antimicrobial agent.
Macrobid is an important drug of triple therapy in the eradication of H. pylori.
Recommended regimens for Helicobacter pylori eradication
Lansoprazole (Zoton) 30mg BID
Clarithromycin (Macrobid) 500mg BID
Amoxicillin (Genamox-500mg x 2) 1gm BID
|
