Prophylactic use of Antibiotics | Prophylaxis Treatment against disease | MCQ on Antibiotics | скачать в хорошем качестве

Prophylactic use of Antibiotics | Prophylaxis Treatment against disease | MCQ on Antibiotics |

This refers to the use of AM As for preventing the setting in of an infection or suppressing contacted infection before it becomes clinically manifest. The latter is also called 'preemptive therapy ', which capitalizes on the small population of pathogen in the body before the disease is manifest. AM As are frequently given prophylactically, but in a number of circumstances this is at best wasteful if not harmful. The difference between treating an infection and preventing it is that treatment is directed against a specific organism infecting an individual patient (targeted therapy), while prophylaxis is often against all organism that may cause infection. The valid as well as improper prophylactic uses may be categorized as: 1. Prophylaxis against specific organisms: This in general is highly satisfactory and the choice of drug is clearcut, because it is targeted. (a) Rheumatic fever: Benzathine penicillin is the drug of choice for preventing infection by group A streptococci which cause recurrences. (b) Tuberculosis: Children. HIV positive and other susceptible contacts of open cases need to be protected. lsoniazid alone for 6 months is recommended. (c) Mycobacterium avium complex (MAC): HI V/AIDS patients with low CD4 count may be protected against MAC infection by azithromycin/clarithromycin. (d) HIV infection: Health care workers exposed to blood by need le stick injury are to be protected by tenofovir + emtricitabine ± lopinavir or atazanavir. The offspring of HIV positive pregnant woman can be protected by treating the woman with tenofovir + lamivudine + efavirenz. After delivery the neonate should be given syrup nevirapine for 6 weeks. (e) Meningococcal meningitis: during an epidemic, especially in contacts; rifampin/ciprofloxacin/ ceftriaxone may be used. (f) Gonorrhoea/syphilis: before or immediately after contact: ampicillin/ceftriaxone. (g) Recurrent genital herpes simplex: Acyclovir prophylax is may be given when four or more recurrences occur in a year. (h) Malaria: Travellers to endemic areas with high trans mission rate many be covered by mefloquine or doxycycline. (i) Influenza A2 or H INI (swine flu): during an epidemic, especially (j) Cholera: tetracycline prophy lax is may be given to close contacts of a case. (k) Whooping cough: non-immunized child contact during the incubation period: erythromycin or azithromycin can abort clinical disease. (I) Plague: Doxycycline prophylax is is recommended for contacts during an epidemic. (m) Pneumocystis jirveci pneumonia: Transplant recipients on immunosuppressants/leukaemia or AIDS patients may be protected by cotrimoxazole. 2. Prevention of infection in high risk situation: such use o f AMAs may be valid and satisfactory in certain situations, but is controversial in others. (a) Dental extraction, tonsillectomy, endoscopies cause damage to mucosa harbouring bacteria and induce bacteremia. This is harmless in most subjects, but in those with valvular defects, this can cause endocarditis. Appropriate prophylaxis with amoxicillin or clindamycin may be given few hours before to few hours after the procedure. (b) Catheterization or instrumentation of urinary tract: prophylaxis with cotrimoxazole or norfloxacin decreases the risk of urinary tract infection (UTI). Patients with cardiacvalvular lesions may be protected with ampicillin, gentamicin or vancomycin during catheterization. (c) To prevent recurrences of UTI in patients with abnormalities of the tract: cotrimoxazole or nitrofurantoin may be given on a long-term basis since the organism mostly is £. coli. (d) Chronic obstructive lung disease, chr nic bronchi tis: ampicilline/doxyeycIine/ciprofloxacin have been used to prevent acute exacerbations; but are of doubtful value. (e) lmmunocompromized patients (receiving corticosteroids or antineoplastic chemotherapy or immunosuppressants after organ transplantation,in neutropenic patients): penicillin/cephalosporin ± an aminoglycoside or fluoroquinolone are often used to prevent respiratory tract infections and septicaemia, but incidence o r superinfections is high. 3. Prevention of infection in general This is highly unsatisfactory in most cases and must be condemned. Examples are: (a) Neonates, especially after prolonged or intrumental delivery. (b) To prevent postpartum infections in the mother after normal delivery. (c) Viral upper respiratory tract infections: to prevent secondary bacterial invasion. (d) To prevent respiratory infections in unconscious patients or in those on respirators. Anitmicrobial agent Pharmacology    • Tetracycline ADR & Uses Mnemonics by using...   FACEBOOK:   / vivekjainsir   You tube Channel Link:    / tutorboxchannel  .