Category III These are new cases of smear negative pulmonary TB With less severe form of extrapulmonary TB, viz,skin Bone,peripheral joint TB. Category IV These are chronic cases who have become smear Positive after completing fully supervised retreatment. These are mostly MDR cases.(multi drug resistant)
TB Category Initial phase Continuation phase Total duration I 2 HRZE (S) 4 HR/ 4 H 3 R 3 Or 6 HE 6 8 II 2 HRZES + 1 HRZE 5 HRE or 5H 3 R 3 E 3 8 8 III 2 HRZ 4 HR/ 4 H 3 R 3 0r 6 HE 6 8 IV Chronic case
In chronic case therapy depends upon the drugs used in the earlier regimen,dosage and regularity with which they were taken, presence of associated disease like AIDS/diabetes/leukemia etc. TB in pregnant women HRZ & E are safe to foetus. Standard 6 month regimen 2HRZ+ 4HR should be given.
a) Polyenes: Amphotericin B, Nystatin
b) heterocyclic benzofuran: Griseofulvin
a) Imidazoles(topical)- Clotrimazole, miconazole
b) Triazoles (systemic)- Fluconazole,itraconazole
Other topical agents Tolnaftate, benzoic acid, sodium thiosulfate. Amphotericin B Source- streptomyces nodosus. MOA- Combine with the ergosterol present in the fungal cell membrane and form a micropore thus increase the cell permeability. USE Topically for oral and cutaneous candidiasis.
DOSE- orally 50-100 mg QID
Source- Penicillium griseofulvum
Active against Epidermophyton,Trichophyton,
Interferes with mitosis
Causes abnormal metaphase configurations.
Systemically only for dermatophytosis
125- 150 mg QID with meals
Imidazole and triazoles
Have broad spectrum antifungal activity
Inhibit funga cytochrome P450 enzyme lanosterol
14-demethylase & thus impair ergosterol synthesis
leading to a cascade of membrane abnormalities in the
DISEASE DRUGS 1 st choice 2 nd choice Candidiasis FLU/NYS/CLO ITR Histoplasmosis AMB FLU Blastomycosis ITR/AMB KTZ/FLU Sporotrichosis AMB ITR
Viruses not only take the nutrition from host cell but
also direct its metabolic machinery to synthesize new
Idoxuridine, Acyclovir, Ganciclovir, Foscarnet
a) Nucleoside reverse transcriptase inhibitors (NRTIs)
b) Nonnucleoside reverse transcriptase inhibitors (NNRTIs)
c) Protease inhibitors
3. Anti-influenza virus
4. Nonselective antiviral drugs
ACYCLOVIR (deoxyguanosine analogue) MOA Acyclovir Herpes virus specific thymidine kinase Acyclovir monophosphate Cellular kinase Acyclovir triphosphate Inhibits herpes virus DNA Gets incorporated in viral DNA Polymerase competatively & stops lengthening of DNA strand.the terminated DNA inhibits DNA-polymerase irreversibly.
Zidovudine (Thymidine analogue)
Single stranded viral RNA
virus directed reverse transcriptase
Double stranded viral DNA
b) NNRTIs Nevirapine & Efavirenz MOA - They directly inhibit HIV reverse transcriptase without the need for intracellular phosphorylation. Their locus of action on the enzyme is also different. c) Protease inhibitors Ritonavir, Nelfinavir MOA- protease act at the late step in HIV replication. They bind to protease molecule and interfere with its cleaving function.
HIV treatment guidelines HAART - highly active antiritroviral therapy Combination of 3 or more drug replace monothrerapy. Therapeutic regimens 2-NRTIs + 1-PI 2-NRTIs + 1-NNRTI 3- NRTIs
Anti-influenza virus Amantadine Inhibits replication of influenza A virus Nonselective Antiviral Drugs Ribavirin - Purine nucleoside analogue - Its mono & triphosphate derivatives generated Intracellularly inhibit GTP and viral RNA synthesis.