ANTI TUBERCULAR DRUGS
PREPARED BY MR. ABHIJIT DAS
TUBERCULOSIS
Tuberculosis
is a serious infectious bacterial disease, caused by mycobacterium
tuberculosis, which mainly affects the lungs.
TB
spreads from person to person through air.
When
a person develops active TB disease, symptoms (such as cough, fever, night
sweats or weight loss) may be mild for many months.
CLASSIFICATION OF ANTITUBERCULAR
DRUGS:
FIRST
LINE DRUGS
1. Isoniazid
2. Rifampin
3. Pyrazinamide
4. Ethambutol
5. Streptomycin
SECOND
LINE DRUGS
1. Thiacetazone
2. Paraaminosalicylic
acid
3. Ethionamide
4. Cycloserine
5. Kanamycin
6. Amikacin
7. Capreomycin
FIRSTLINE DRUGS:
These drugs have high anti tubercular efficacy as well as low toxicity.
SECOND LINE DRUGS:
These drugs have low efficacy and high toxicity.
FIRST LINE ANTI TUBERCULAR DRUGS
ISONIAZIDE (ISONICOTINIC ACID HYDRAZIDE)
Isoniazide
is an essential component of all anti tubercular resimens. It is primarily tuberculocidal.
It
is one of the cheapest anti tubercular drugs.
MECHANISM
OF ACTION
Isoniazid
inhibits the synthesis of mycolic acids which
are unique components of bacterial cell wall.
ADVERSE
EFFECTS
1. Peripheral
neuritis
2. Mental
disturbances
3. Hepatitis
4. Arthralgia
(joint pain)
RIFAMPICIN
It
is a tuberculocidal as well.
MECHANISM
OF ACTION
Rifampicin
inhibits DNA dependent RNA synthesis.
ADVERSE
EFFECTS
1. Hepatitis
2. Breathlessness
3. Haemolysis
4. Rashes,
redness and watering of eyes.
ETHAMBUTOL
Ethambutol
is tuberculostatic.
MECHANISM
OF ACTION
It
inhibits mycolic acid incorporation in mycobacterial cell wall. So it works by
inhibiting cell wall synthesis.
ADVERSE
EFFECTS
1. Rashes
2. Fever
3. Nausea
STREPTOMYCIN
It
was the first clinically useful antitubercular drug.
It
is tuberculocidal, but less effective than
isoniazid or rifampin.
MECHANISM
OF ACTION
Streptomycin
blocks the ability of ribosomes to make proteins.
ADVERSE
EFFECTS
1. Stomach
upset
2. Lack
of appetite
3. Vertigo
4. Chest
pain