Tetracyclines Methotrexate

P-gp (ABCB1) Verapamil, digoxin, mitoxantrone, vinblastine, doxorubicin, losartan, talinolol, cortisol, dexamethasone, colchicine, loperamide, domperidone, indinavir, erythromycin, tetracycline, itraconazole, cyclosporine, methotrexate, amitryptyline, phenobarbital, morphine, cimetidine, and others... 

Oral administration of bicarbonate may decrease the absorption of ketoconazole. Increased blood levels of quinidine, flecainide, or sympatiiomimetics may occur when these agents are administered with bicarbonate There is an increased risk of crystalluria when bicarbonate is administered with the fluoroquinolones. Fbssible decreased effects of lithium, methotrexate, chlorpropamide, salicylates, and tetracyclines may occur when these drag s are administered with sodium bicarbonate. Sodium bicarbonate is not administered within 2 hours of enteric-coated drugs the protective enteric coating may disintegrate before the drug reaches the intestine. 

Drugs that may interact include chlorpropamide, lithium, methotrexate, salicylates, tetracyclines, anorexiants, flecainide, mecamylamide, quinidine, and sympathomimetics. 

Tetracycline Tetracycline injections have an acid pH. Incompatibility may reasonably be expected with alkaline preparations or with drugs unstable at low pH. Care should be taken when administering tetracyclines, since chelation takes place with metal ions. Tetracyclines interact with inorganic metal ions. They should not be used with drugs that cause hepatotoxicity and nephrotoxicity (e.g., digoxin, theophylline, ergot alkaloids, methotrexate, oral contraceptives, and penicillins). 

Mercaptopurine Methotrexate Oral contraceptives p-Ami nosalicylate Phenobarbital Phenyloin Primidone Pyrimethamine Sulfasalazine Tetracycline Vinblastine... 

These include mesalazine, metformin, NSAIDs, tetracyclines (except doxycycline and minocycline), chloramphenicol, lithium, methotrexate, chloroquine, fibrates, chlorpropamide and glibenclamide, Clinically, it is useful to measure urine output per hour or per 24 hours as a fall in urine output in the presence of adequate fluid intake often indicates or warns of some impairment of renal function. Furthermore, it is neither expensive nor time-consuming to perform a quick test for albumin, casts and red cells in the urine, and to measure pH. Creatinine clearance values are often used to determine the safe doses for several drugs (e.g. NSAIDs, ciclosporin). 

A review of the literature shows that photochemical reactions generally follow first-order kinetics. However, pseudo first-order, zero-order, and even fractional-order kinetics have been reported. Drugs reported to follow first-order kinetics include nifedipine (8) doxepin (41), riboflavin (28), minoxidil (48), adriamycin (52), doxorubicin, daunorubicin and epirubicin (61), folic acid (66), menadione sodium bisulfite (67), tetracycline hydrochloride (71), decarbazine (73), furosemide (74), democlocycline (76) and hydrocortisone, and prednisolone (90). Apparent pseudo first-order rate has been reported for pyridoxine (84). Indomethacin (91), sodium nalidixate (65), methotrexate (92), and metronidazole (68) have been reported... 

P-Lactam antibiotics Cephalosporins Cidofovir Furosemide Ganciclovir Methotrexate NSAIDs Probenecid Tetracycline Zidovudine KW-3902 ... 

Clinically important, potentially hazardous interactions with allopurinol, bromelain, chloramphenicol, demeclocydine, doxycydine, erythromycin, imipenem/cilastatin, methotrexate, minocycline, oxytetracycline, sulfonamides, tetracycline... 

Oat2 Benzylpenicillin, erythromycin, tetracycline, rifampicin, glibenclamide, tolbutamide, zidovudine, ganciclovir, digoxin, enalapril, verapamil, methotrexate, acetylsalicylic add... 

Transporter absorptive effects predominant Examples. Acyclovir, Amiloride -, Amoxicillin Atenolol Atropine, Bidisomide Bisphosphonates Captoprit, Cefazolin Cetirizine Cimetidine Ciprofloxacin, Cloxacillin Dicloxacillin Erythromycin - -, Famotidine Fexofenadine Folinic acid Furosemide, Ganciclovir Hydrochlorothiazide, Lisinopril Metformin Methotrexate, Nadolol Penicillins Pravastatin Ranitidine Tetracycline Trimethoprim Valsartan Zalcitabine... 

Pulmonary infiltrates with eosinophilia (Loeffler s syndrome) have been associated with nitrofurantoin,para-aminosalicytic acid, methotrexate, sulfonamides, tetracycline, chlorpropamide, phenytoin, NSAIDs, and imipramine (Table 29-5). The disorder is characterized by fever, nonproductive cough, dyspnea, cyanosis, bilateral pulmonary infiltrates, and eosinophilia in the blood. Lung biopsy has revealed perivasculitis with infiltration of eosinophils, macrophages, and proteinaceous edema fluid in the alveoli. The symptoms and eosinophilia generally respond rapidly to withdrawal of the offending drug. 

Increased risk of bleeding with anticoagulants. Increased risk of Gl ulceration with alcohol, corticosteroids, phenylbutazone, oxyphenbutazone. Decreases uricosurea effects of probenecid and sulfinpyrazone and diuretic effects of spironolactone. Decreases absorption of tetracycline. Increases plasma levels of methotrexate. 

Tetracyclines destroy the bacterial flora necessary for the breakdown of methotrexate. This results in t free methotrexate concentrations. Tetracyclines are also considered to inhibit the elimination of methotrexate and allow a build-up of methotrexate in the bladder. The effect of the interaction is often delayed... 

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