Tetracycline nephrotoxicity

Rena] toxicity One form of renal tubular acidosis, Fanconi s syndrome, has been attributed to use of outdated tetracyclines. Though not directly nephrotoxic, tetracyclines may exacerbate preexisting renal dysfunction. 

There is an increased risk of toxicity of MTX when administered with the NSAIDs, salicylates, oral antidiabetic drugs, phenytoin, tetracycline, and probenecid. There is an additive bone marrow depressant effect when administered with other drug known to depress the bone marrow or with radiation therapy. There is an increased risk for nephrotoxicity when MTX is administered with other drug that cause nephrotoxicity. When penicillamine is administered with digoxin, decreased blood levels of digoxin may occur. There is a decreased absorption of penicillamine when the dmg is administered with food, iron preparations, and antacids. 

Outdated products Under no circumstances should outdated tetracyclines be administered the degradation products of tetracyclines are highly nephrotoxic and have, on occasion, produced a Fanconi-like syndrome. 

Two tetracyclines have sufficiently distinctive features to warrant separate mention. Doxycycline, with its longer half-hfe and lack of nephrotoxicity, is a popular choice for patients with preexisting renal disease or those who are at risk for developing renal insufficiency. The lack of nephrotoxicity is related mainly to biliary excretion, which is the primary route of doxycycline elimination. Doxycycline is the preferred parenteral tetracycline Doxycycline is a potential first-hne agent in the prophylaxis of anthrax after exposure. Doxycycline is the treatment of choice for the primary stage of Lyme disease in adults and children older than 8 years. 

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... 

Minocycline (Solodyn) [Anribiotic/Tetracycline] Uses Acne Action Tetracycline, bacteriostatic Dose Adults Peds >12y. 1 mg/kg PO daily x l2wk w/ food to X- irritation Caution [C, ] assoc w/ pseudomembranous colitis w/ renal impair Contra Allergy, women of childbearing potential Disp Tabs SE D, HA, fever, rash, joint pain, fatigue, dizziness Interactions T Effects OF digoxin, oral anticoagulants T risk of nephrotox W/ methoxyflurane X- effects W/... 

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). 

Before the introduction of specific vasopressin receptor antagonists, pharmacological treatments for hyponatremia centered on the use of loop diuretics and nonspecific inhibitors of vasopressin signaling, such as lithium carbonate and demeclocycline.11 The utility of such therapies has been limited by a range of sideeffects. Loop diuretic use can result in electrolyte imbalances and suffers from poor response predictability.11 Lithium carbonate suffers from a low therapeutic index and a risk of renal damage as well as limited effectiveness in many patients. Lithium carbonate has therefore been nearly completely supplanted by demeclocycline, a tetracycline antibiotic, in the treatment of chronic hyponatremia.12 Demeclocycline use is itself limited by its nephrotoxicity (particularly in cirrhotic patients), ability to cause reversible uremia, and ability to induce photosensitivity.1,11... 

CICLOSPORIN TETRACYCLINES -DOXYCYCLINE t levels of ciclosporin leading to risk of nephrotoxicity, hepatotoxic-ity and possible neurotoxicity such as hallucinations, convulsions and coma The mechanism is not known, but doxycydine is thought to t ciclosporin levels Concomitant use in transplant patients should be well monitored, with frequent ciclosporin levels. In non-transplant patients, renal function should be monitored closely and patients warned about potential side-effects such as back pain, flushing and gastrointestinal upset. The dose of ciclosporin should be 1 appropriately... 

Tetracyclines can cause gastric irritation, particularly in large doses, and can also cause tooth discoloration in children. Hepatotoxicity may be seen with large doses (> 2g), as well as nephrotoxicity. Hypersensitivity reactions can also be seen. 

Drugs with nephrotoxic potential include ACE inhibitors, acetazolamide. aminoglycosides, aspirin, amphotericin B, cyclosporine, furosemide, gold salts, lithium, methicillin, methoxyflurane, NSAIDs, pentamidine, sulfonamides, tetracyclines (degraded), thiazides, and triamterene. 

Tetracyclines 5-12 h > 1 g/d in infants Benign intracranial hypertension. Degradation products (eg, expired prescription) are nephrotoxic, may cause Fanconi-like syndrome. Some products contain sulfites. 

The risk of nephrotoxicity with methoxyflurane would therefore appear to be increased by some of these drugs and the concurrent use of tetracycline or nephrotoxic antibiotics should be avoided. Similarly, methoxyflurane should only be used with great caution, if at all, following the chronic use of hepatic enzyme-inducing drugs. 

Not understood. One suggested reason for increased serum-lithium levels is that tetracycline (known to have nephrotoxic potential) may have adversely affected the renal clearance of lithium. ... 

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