Tetracyclines Warfarin

Clinically important, potentially hazardous interactions with aspirin, ciprofloxacin, doxycycline, hypoglycemics, lomefloxacin, lymecycline, methotrexate, minocycline, tetracycline, warfarin... 

Bloating, constipation, l absorption of digoxin, thiazides, tetracyclines, warfarin, and vitamin K. 

The effects of warfarin may increase when administered with acetaminophen, NSAIDs, beta blockers, disulfiram, isoniazid, chloral hydrate, loop diuretics, aminoglycosides, cimetidine, tetracyclines, and cephalosporins. Oral contraceptives, ascorbic acid, barbiturates, diuretics, and vitamin K decrease the effects of warfarin. Because die effects of warfarin are influenced by many drugp, die patient must notify die nurse or die primary healdi care provider when taking a new drug or discontinuing... 

Medical drugs Antibiotics (tetracyclines), anticancer drugs, anticonvulsants (valproic acid), lithium, retinoids (vitamin A), thalidomide, diethylstilbestrol (DES), anticoagulants (warfarin)... 

Synergism Increased anticoagulation of warfarin with clofibrate, corticosteroids, tetracycline, vitamin K and naloxone. 

Absorption of certain drugs, including those with neutral or cationic charge as well as anions, may be impaired by the resins. These include digitalis glycosides, thiazides, warfarin, tetracycline, thyroxine, iron salts, pravastatin, fluvastatin, folic acid, phenylbutazone, aspirin, and ascorbic acid. Any additional medication (except niacin) should be given 1 hour before or at least 2 hours after the resin to ensure adequate absorption. Colesevelam does not bind digoxin, warfarin, or reductase inhibitors. 

Rx of pneumonia, skin, soft tissue Infxns, osteomyelitis caused by penicillinase-producing staphylococci Action Bactericidal X cell wall synth Dose Adults. 250-500 mg qid Feds <40 kg, 12.5-100 mg/kg/d - qid take on empty stomach Caution [B, ] Contra Component orPCN sensitivity Disp Caps 125, 250, 500 mg soln 62.5 mg/5 mL SE N/D, abd pain Interactions T Effects W/ disulfiram, probenecid T effects OF MRX, X effects W/ macrolides, tetracyclines, food X effects OF OCPs, warfarin EMS Monitor for signs of electrolyte disturbances and hypovolemia d/t D OD May cause N/V/D, behavior changes, urinary retention, skin rash and Szs symptomatic and supportive... 

Doxycydine (Adoxa, Periostal-, Oracea, Vibramycin, Vibra-Tabs) [Anribiotic/Tetracycline] Uses Broad-spectrum antibiotic acne vulgaris, uncomplicated GC, Chlamydia sp, PID, Lyme Dz, skin Infxns, anthrax, malaria prophylaxis Action Tetracycline bacteriostatic X- protein synth Dose Adults. 100 mg PO ql2h on 1st d, then 100 mg PO daily bid or 100 mg IV ql2h acne daily dosing, Chlamydia 7d, Lyme Dz 14—21 d, PID 14 d Peds >8 y 5 mg/kg/24 h PO, to a max of 200 mg/d - daily-bid Caution [D, +] Hepatic impair Contra Children <8 y, severe hepatic dysfxn Disp Tabs, caps, syrup, susp, inj SE D, GI disturbance, photosens Interactions T Effects OF digoxin, warfarin 1 effects W/ antacids, Fe, barbiturates, carbamazepine, phenytoins, food 4-effects OF penicillins EMS Monitor for signs of electrolyte disturbances and hypovolemia d/t D monitor for S/Sxs of super Infxn T risk of photosensitivity Rxns antibiotic of choice for the Tx and prophylaxis of anthrax exposure expired tetracyclines have been known to cause nephrotox OD May cause adverse GI effects symptomatic and supportive... 

Apart from being a diffusional barrier, mucin can also interact with drugs to decrease their bioavailability, as has been shown with tetracycline [106], phenylbutazone, and warfarin [107]. On the other hand, studies in rats showed that binding of some water-soluble drugs to intestinal mucus was essential for their absorption and that damage to the mucus significantly reduced absorption [108], The acidic mucus is essential for lipid absorption and could be important for the diffusion of lipophilic drugs (see below). 

Aminophylline Aminophylline should not be mixed with acidic drugs, as it becomes precipitated if the pH of the final solution falls below pH 8. Mixture with glucose may increase the pH above 10 where proteins, such as insulin and erythromycin, are unstable. Some drugs that are incompatible with aminophylline include amiodarone, benzylpenicillin potassium, cisatracurium, ceftazidime, ceftriaxone, dobutamine, tetracycline hydrochloride, verapamil hydrochloride, warfarin sodium, and vitamin B and C injection. Alcohol-free theophylline should be stored in amber-colored containers maximum care must be taken to protect it against exposure to light.92-94... 

Warfarin sodium may be adsorbed to PVC and intravenous infusion sets but may be minimized with glass containers or polyethylene-lined containers. Warfarin sodium is incompatible with solutions of adrenaline hydrochloride, amikacin sulfate, metaraminol tartrate, oxytocin, promazine hydrochloride, tetracycline hydrochloride, aminophylline, bretylium tosylate, ceftazidime, cimetidine hydrochloride, ciprofloxacin lactate, dobutamine hydrochloride, esmolol hydrochloride, gentamicin sulfate, labetalol hydrochloride, metronidazole hydrochloride, and vancomycin hydrochloride.130131... 

Westfall LK, Mintzer DL, Wiser TH. Potentiation of warfarin by tetracycline. Am J Hosp Pharm 1980 37(12) 1620. 

Danos EA. Apparent potentiation of warfarin activity by tetracycline. Clin Pharm 1992 ll(9) 806-8. 

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