The tetracycline antibiotic family provides broad anti-bacterial protection by inhibiting bacterialprotein synthesis. The mammalian host's protein synthesis mechanisms are not affectedbecause of basic differences in the shape of the cellular machinery (the ribosomes) used totranslate RNA into protein.
The body possesses many barriers through which antibiotics have difficulty penetrating (thenervous system, prostate gland, and eye are some examples). Infections behind these barriers can be difficult to treat. Doxycycline represents a modification of the basic tetracyclinestructure to enhance its ability to penetrate such biological barriers and to increase its duration of action. Though unable to reach adequate concentrations in the central nervous system,doxycycline is able to penetrate the prostate gland to treat infections there and can permeatecells to address intracellular parasites. Infectious agents for which members of the tetracyclinefamily are especially helpful are, as mentioned, the intracellular ones including:
• Hemobartonella felis (agent of Feline Infectious Anemia)• Borrelia bergdorferi (agent of Lyme's disease)• Chlamydia psittaci (an agent of feline upper respiratory infection)• Ehrlichia species (a tick-borne organism)• Mycoplasma species (in upper respiratory & urinary infections)• Doxycyline has been used in the treatment of heartworm infection, not to kill the worms
but to kill the Wolbachia
bacteria carried by the heartworms. Wolbachia
may increase thetendency for embolism to complicate heartworm disease treatment so killing theWolbachia
prior to killing the adult heartworms is often included in the heartwormtreatment protocol.
Doxycycline has also proven useful in combating "methicillin-resistant Staph aureus" (human)and "methicillin-resistant Staph intermedius" (pet) infections. These infections involveStaphylococci (bacteria) which are resistant to the drugs that Staphylococci have previouslybeen predictably sensitive to.
Of course, there are plenty of less exotic bacteria against which doxycycline may be used.
These include: Bordetella bronchiseptica (the chief agent of Kennel Cough) and bacteria ofthe genus Brucella.
Doxycycline also has properties by which it modifies immune-mediated diseases. This"immuno-modulating" effect is separate from its antibacterial effects and is useful in treatingsuch conditions as: discoid lupus erythematosus, plasma cell pododermatitis, and otherimmune-mediated skin diseases. Often doxycycline is combined with the B vitamin,niacinamide, to enhance results in such situations.
Nausea and vomiting are the most commonly reported side effects of Doxycycline in dogs and cats. If this side effect occurs, it is most easily managed by giving the medication with food.
(Other members of the Tetracycline class should not be given with food as food binds the drug and prevents its absorption into the body. With Doxycycline this is effect is not consideredsignificant.)
Drugs of the Tetracycline class have potential to permanently stain teeth if given to immatureanimals. (It binds to calcium which is needed for growing bones and teeth.) Doxycycline hasthe least potential for doing this.
Antacids commonly contain calcium, which binds Doxycycline in the GI tract. If thesemedications are used together, neither may be absorbed properly and the benefits of both arelost. Iron containing vitamin supplements produce the same problem. (Iron supplementsmight well be used with Doxycycline to treat "Feline Infectious Anemia.” Administration of these two medications should be separated by a couple of hours or an injectable iron supplementmay be employed.)
Nausea may result if Doxycycline is used in combination with theophylline (an airway dilator).
These two drugs might be used together to treat "Kennel Cough."
Drugs of the tetracycline class may make Digoxin (a heart medication) act stronger, thusallowing a reduction in dose.
The Doxycycline oral liquids do not require refrigeration.
The reconstituted oral suspension is only good for 2 weeks. After that, it must be discarded.
Doxycycline does not kill bacteria, it merely curtails their ability to reproduce. For the invadingbacteria to be killed, the host's immune system must be active and effective. This may not bethe best choice medication for immune compromised patients.
Doxycycline oral liquid is made for human children and is thus raspberry flavored. Someanimals (particularly cats) do not like this taste. Doxycycline tablets are not flavored.
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Properties and Performance of Rear Screen MaterialsStewart AeroGlas 100 vs. Da Lite DA 100 WAOne area of the audio visual industry that requires further study involves published specifications of products and how these specifications relate to the products as delivered and their actual performance in systems integration. The two areas of concern in our current studies involves video projectors a
Peritoneal Dialysis International, Vol. 20, pp. 396–411Printed in Canada. All rights reserved. Copyright © 2000 International Society for Peritoneal Dialysis ISPD GUIDELINES/RECOMMENDATIONS ADULT PERITONEAL DIALYSIS-RELATED PERITONITIS TREATMENT RECOMMENDATIONS: 2000 UPDATE William F. Keane,1 George R. Bailie,2 Elizabeth Boeschoten,3 Ram Gokal,4 Thomas A. Golper,5Clifford J. Holmes,