Tetracyclines

Are tetracylines bacteriostatic or bactericidal?

Bacteriostatic

Why do tetras depend on a functional immune system?

Because they are generally bacteriostatic

Why should tetracycline & oxytetracycline be avoided in the first few week of an animals life while adult teeth are being developed?

Because they can cause discoloration of the tooth enamel & dentin causing a yellow color. They may also cause slow bone development since they bind with calcium in high doses

How should tetracycline be administered?

By mouth

What is the process by which one compound binds to another compound, resulting the compounds to precipitate out of solution?

Chelation

What needs to be done to the dose if there is any change in the kidney function?

Decrease the dose

What can happen in dogs even if superinfections do not occur?

Diarrhea, vomiting, & anorexia.

Which 2 tetras are more lipophilic?

Doxycycline & Minocycline

What is the process in which tetracycline & oxytetracycline can be reabsorbed back into the body?

Enterohepatic circulation (movement from the intestine to the liver & back)

True or False. Oral Tetracylines can kill off significant numbers of normal ruminal flora resulting in hypermotility of the rumen and reticulum.

False; it causes Ruminal-reticular stasis

What signs do cats show?

Fever, depression, abdominal pan.

With what type of diet should oral tetracyclines not be administered?

High Calcium

What animal does small dose IV injections cause cardiac arrhythmias, collapse, & death?

Horses

Where is Doxycycline largely excreted?

Intestine

What is the longer acting injectable form of Oxytetracycline called?

LA-200; it is administered with a longer dose interval of 2-3 days

What are the newer tetracyclines?

More lipophilic Doxycycline & Monocycline. They're used more frequently due to their longer half-life, broader spectrum of antibacterial action, & better penetration of tissues.

Does Doxycycline cause the same discoloring effect as tetra & oxytetra?

No

Are mammalian cells ribosomes able to bind with tetras?

Only if the dosage is high enough, protein synthesis might be affected

Which tetra is most commonly used as an IM injection

Oxytetracycline

What are tetracyclines commonly used to treat?

Rickettsial diseases (Rocky Mountain Spotted Fever in humans), Ehrlichiosis & salmon poisoning in dogs, hemobartonellosis in dogs & cats, Mycoplasma pneumonia, chlamydial infections (ocular in cats), psittacosis in birds, & borreliosis (Lyme disease) Also can be used in tear staining in dogs

What can orally administered tetras cause?

Superinfections from an overgrowth of pathogenic bacteria in the gut

What are the older tetracyclines? Are they hydrophilic or lipophilic?

Tetracycline & Oxytetracycline; Hydrophilic

What class of ab's are most commonly prescribed to treat Rickettsial infections, such as Rocky Mt. Spotted Fever?

Tetracyclines

Why are tetracycline & oxytetracycline not okay to take with dairy products?

They are readily chelated by divalent cations or trivalent cations,

How do tetracyclines kill bacteria?

They bind to bacterial ribosomes & prevent RNA from linking to the ribosomes, which disrupts protein synthesis.

What happens when tetras & oxytetras expire?

They decompose to form a nephrotoxic compound that damages cells of the kidneys proximal convoluted tubule, resulting in Fanconi's syndrome.

Can food be given with doxycycline?

Yes, to decrease GI side effects.

How are tetracyclines & oxytetracyclines excreted?

by filtration through the kidneys & lesser extent through the liver

What can tetras cause in ruminants?

high oral doses can kill off significant numbers of normal ruminal flora causing rumino-reticular stasis.

Are many bacteria currently resistant to tetracyclines?

yes