Mastitis therapy: To combine or not to combine antibiotics? by Dr Laurent Goby, Boehringer Ingelheim Animal Health GmbH, Jawetz's law on antimicrobial combination Ingelheim, Germany.
Bactericidal + bactericidal: may be synergistic or additive.
Antibioticsareusuallypro- narrowspectrumagents(active
Bacteriostatic + bacteriostatic: usually additive.
Bacteriostatic + bactericidal: may be antagonistic or indifferent.
nistic, indifferent or inefficacious.
either bactericidal or bacteriostatic. Antimicrobial combinations
involving antibiotic resistant strains. Fight against bacteria
Synergism can be defined as the positive interaction of two or more agents
so that their combined effect is significantly greater than the expected sum
of their individual effects (1 + 1 = 3).
Antagonism is a negative interaction between two drugs; the combined
effect of their combination is significantly less than the sum of the respective
effect when tested separately (1+1=1).
Additivity assumes that the result observed with more than one drug
should be the sum of the separate effects of the drug being tested if those
the activities of the individual agents.
drugs do not interact with one another (1+1=2).
nary medicine, it is still not very clear
exceptions to the so-called ‘Jawetz’s
Interactions investigated Narrow spectrum of activity
A narrow spectrum antibiotic is effective against a relatively defined small
subset of bacteria only a few Gram positive or Gram negative.
Penicillin is an example of an antibiotic possessing a highly efficient but
narrow spectrum of activity, acting particularly against Gram positive bacte-
ria (bacteria that have a cell wall composed of a thick layer of a particular
substance that retains the colour of the crystal violet stain in the Gram
stain. The Gram positive bacteria include staphylococci and streptococci.
Use of a narrow spectrum antibiotic allows an avoidance of some of the
destruction of normal flora usually associated with antibiotic use.
International Dairy Topics — Volume 7 Number 5
Family of Spectrum Main target antibiotic representatives of activity organisms
compounds or compared to otherantibiotics. In most cases, compara-
however, reported as being some-times associated with a lower rate of
tial treatment). Proof of clinicallyimportant antimicrobial synergy
of antibiotic combinations in anattempt to produce bactericidal syn-
be used successfully to provide abroad spectrum of activity or in the
References
● Gunnison J. B. et al (1953). Studies on antibiotic synergism
vitro of combinations of antibi-otics on bacteria of varying resis-
treatment of clinical mastitis withone of three intramammary antibi-
● Mouton J. W. et al. (1999). Useof Pharmacodynamic Indices To
Table 1. Antibacterial drugs used for mastitis treatment.
International Dairy Topics — Volume 7 Number 5
A holistic perspective of security in Health related Virtual Communities I. Apostolakis1, A. Chryssanthou2, I. Varlamis3 Department of Computer Science and Technology Abstract A significant issue in health related applications is protecting a patient’s profile data from unauthorized access. In the case of telemedicine systems a patient’s medical profile and other medical informa
WCAT Decision Number : WCAT-2008-02320 WCAT Decision Date: _____________________________________________________________________ Introduction The worker appeals from four decisions of review officers of the Workers’ Compensation Board, operating as WorkSafeBC (Board). The” A” appeal is from the decision of a review officer dated January 17, 2007 ( Review Decision #R0069683 )