infectious diseases
Antifungal Medications
Amphotericin B
 does not have good cerebrospinal fluid penetration, it is still effective for certain mycoses such as Cryptococcal meningitis . There are 2 formulations ofamphotericin B: Deoxycholate (standard) Lipid-based Thestandard formulation,amphotericin Bdeoxycholate, must always be given in 5% D/W because salts can precipitate the drug. It is usually given over 2 to 3 hours, although more rapid infusions over 20 to 60 minutes can be used in selected patients. However, more rapid infusions usually have no advantage. Many patients have chills, fever, nausea, vomiting, anorexia, headache, and, occasionally, hypotension during and for several hours after an infusion.Amphotericin Bmay also cause chemical thrombophlebitis when given via peripheral veins; a central venous catheter may be preferable. Pretreatment withacetaminophenor nonsteroidal anti-inflammatory drugs is often used; if these medications are ineffective,hydrocortisone25 to 50 mg ordiphenhydramine25 mg is sometimes added to the infusion or given as a separate IV bolus. Often,hydrocortisonecan be tapered and omitted during extended therapy. Severe chills and rigors can be relieved or prevented bymeperidine50 to 75 mg IV. Severallipid vehiclesreduce the toxicity ofamphotericin B(particularly nephrotoxicity and infusion-related symptoms). Two preparations are available: Amphotericin Blipid complex Liposomalamphotericin B Lipid formulations are preferred over conventionalamphotericin Bbecause they cause fewer infusion-related symptoms and less nephrotoxicity. The main adverse effects ofamphotericin Bare Nephrotoxicity (most common) Hypokalemia Hypomagnesemia Bone marrow suppression Renal impairment is the major toxic risk ofamphotericin Btherapy. Serum creatinine and bloodureanitrogen (BUN) should be monitored before treatment and at regular intervals during treatment: several times/week for the first 2 to 3 weeks, then 1 to 4 times/month as clinically indicated. Amphotericin Bis unique among nephrotoxic antimicrobials because it is not eliminated appreciably via the kidneys and does not accumulate as renal failure worsens. Nevertheless, dosages should be lowered or a lipid formulation should be used instead if serum creatinine rises to>2.0 to 2.5 mg/dL (>177 to 221 micromol/L) or BUN rises to>50 mg/dL (>18 millimole/L). Acute nephrotoxicity can be reduced by aggressive IV hydration with saline beforeamphotericin Binfusion; at least 1 L of normal saline should be given beforeamphotericin Binfusion. Mild to moderate renal function abnormalities induced byamphotericin Busually resolve gradually after therapy is completed. Permanent damage occurs primarily after prolonged treatment; after>4 g total dose, approximately 75% of patients have persistent renal insufficiency. Amphotericin Balso may blunt the erythropoietin response and cause anemia. Hepatotoxicity or other untoward effects are unusual. 