Tuesday 2 February 2010

Desferal


Generic Name: Deferoxamine Mesylate
Class: Heavy Metal Antagonists
ATC Class: VO3AC01
VA Class: AD300
Chemical Name: N - [5 - [3 - [(5 - aminopentyl)hydroxycarbamoyl]propionamido]pentyl] - 3 - [[5 - (N - hydroxyacetamido)pentyl]carbamoyl]propionohydroxamic acid monomethanesulfonate (salt)
Molecular Formula: C25H48N6O8.CH4O3S
CAS Number: 138-14-7

Introduction

Heavy metal antagonist; chelating agent for iron118 194 b and aluminum.195 196 197 b


Uses for Desferal


Acute Iron Intoxication


Adjunctive therapy for acute iron intoxication.118 b


Not a substitute for standard measures generally used, including GI decontamination (e.g., induction of emesis, gastric lavage, whole-bowel irrigation), suction and maintenance of airway, correction of acidosis, and control of shock with IV fluids, blood, oxygen, and vasopressors.118 202 b


Recommended for patients with severe manifestations of iron intoxication (e.g., metabolic acidosis, repetitive vomiting, lethargy, coma, seizures, hypotension, GI bleeding, signs of shock) or serum iron concentration >500 mcg/dL; less serious ingestions may be treated with supportive care alone.202 203 204 205 b


Chronic Iron Overload


Treatment of chronic iron overload resulting from multiple transfusions in patients with thalassemia or other chronic anemias.118 194 b


Long-term therapy may have beneficial effects on the liver (i.e., slow accumulation of hepatic iron, retard or eliminate progression of hepatic fibrosis).b


In patients with thalassemia, long-term therapy may have beneficial effects on the heart (e.g., delay and/or prevent development of iron-associated cardiac disease,100 101 128 129 130 132 133 134 improve left ventricular function in patients with subclinical cardiac dysfunction,101 132 improve cardiac function in at least some patients with symptomatic cardiac disease102 ) and improve survival.129 133 134 135


Initiate therapy early in the course of thalassemia (i.e., some clinicians recommend initiation of chelation therapy when serum ferritin concentrations reach 1000 ng/mL or child reaches the age of 3 years133 [see Pediatric Use under Cautions]) and monitor compliance closely; noncompliance with chelation regimen and failure to initiate therapy prior to development of irreversible tissue damage are associated with cardiac disease.129 130 133


Aluminum Toxicity


Diagnosis119 127 195 196 200 201 or treatment of aluminum-associated neurotoxicity and/or bone abnormalities in patients with chronic renal failure undergoing dialysis.104 105 106 107 108 109 126 195 196 197 200 201


Hemochromatosis


Has been used with some success for treatment of iron overload secondary to primary hemochromatosis.b Phlebotomy is the method of choice for removal of excess iron;118 b however, deferoxamine may be beneficial when phlebotomy is contraindicated.b


Other Uses


Has been studied as a chelating agent for aluminum and its potential beneficial effects in patients with Alzheimer’s disease;142 152 153 154 155 156 not currently recommended for this use since existing evidence to support such use is weak and long-term chelation therapy may be associated with potentially serious adverse effects.142 153


Desferal Dosage and Administration


Administration


Administer by IM injection, IV infusion, or sub-Q infusion.118 b


Acute iron intoxication: Manufacturer states that IM injection is the preferred route of administration and should be used for all patients who are not in shock.118 Manufacturer recommends slow IV infusion only for patients with cardiovascular failure or shock, with switch to IM administration as soon as the patient’s clinical condition permits.118 However, most experts recommend IV infusion for intoxications requiring deferoxamine therapy (see Acute Iron Intoxication under Uses).202 203 204 205


Chronic iron overload: Administer by slow sub-Q infusion.118 b May administer IM.118 b


Aluminum toxicity: Generally administered by slow IV infusion.126 195 196 200 201 Has been administered IM or intraperitoneally.107 108 109 149 200 201


IV Administration


Administer by slow IV infusion.118 b


Reconstitution

Reconstitute vial containing 500 mg of deferoxamine mesylate with 5 mL of sterile water for injection or vial containing 2 g of the drug with 20 mL of sterile water for injection to provide solution containing 95 mg/mL.118 Reconstituted solution is for single use only;118 discard unused portion.118


Dilution

Add the required amount of reconstituted solution to 0.9% sodium chloride, 0.45% sodium chloride, dextrose injection, or lactated Ringer's injection.118


Rate of Administration

Rapid IV injection may result in flushing of the skin, generalized erythema, urticaria, hypotension, and shock.118 b Maximum safe rate of administration not scientifically established.159 203


Acute iron intoxication: Empiric maximum rate of 15 mg/kg per hour recommended for the first 1 g118 159 167 169 176 followed by a slower rate of ≤125 mg/hour if needed.118


Aluminum toxicity: Infuse dose over 1 hour.200 201


IM Administration


Reconstitution

Reconstitute vial containing 500 mg of deferoxamine mesylate with 2 mL of sterile water for injection or vial containing 2 g of the drug with 8 mL of sterile water for injection to provide solution containing 210 or 213 mg/mL, respectively.118 Reconstituted solution is for single use only; discard unused portion.118


Sub-Q Administration


Administer by slow sub-Q infusion via a small, portable controlled-infusion device.118


Reconstitution

Reconstitute vial containing 500 mg of deferoxamine mesylate with 5 mL of sterile water for injection or vial containing 2 g of the drug with 20 mL of sterile water for injection to provide solution containing 95 mg/mL.118 Reconstituted solution is for single use only; discard unused portion.118


The reconstituted solution may be infused sub-Q undiluted.b


Rate of Administration

Rate of infusion in patients with chronic iron overload must be individualized, but ranges from 20–40 mg/kg daily infused over 8–24 hours.118 b


Most convenient to administer the drug overnight as an 8- to 12-hour sub-Q infusion.b In some patients, iron excretion will be as high following an 8- to 12-hour infusion as the same dose administered over a 24-hour period.118 b


Dosage


Available as deferoxamine mesylate; dosage expressed in terms of the salt.118


Pediatric Patients


Acute Iron Intoxication

IV or IM

Optimal dosage and duration of therapy not established.202 203 204 205 Consultation with poison control expert recommended in severe intoxications.204 205


Manufacturer recommends 1 g initially; may be followed by 500 mg every 4 hours for 2 doses.118 Subsequent doses of 500 mg may be administered every 4–12 hours depending on clinical response (maximum 6 g in 24 hours).118


Alternatively, initial dose of 20 mg/kg or 600 mg/m2 followed by 10 mg/kg or 300 mg/m2 at 4-hour intervals for 2 doses.b Subsequent doses of 10 mg/kg or 300 mg/m2 may be administered every 4–12 hours as needed.b


Chronic Iron Overload

IM

Usual IM dosage is 0.5–1 g daily.118 b In addition, administer 2 g of the drug by slow IV infusion with, but separate from, each unit of blood transfused (not to exceed 6 g with transfusion, even if ≥3 units of blood or packed RBCs transfused).118


Sub-Q

Usual dosage is 1–2 g (20–40 mg/kg) infused daily.118 b


Aluminum Toxicity

Diagnosis in Patients with CKD

IV

Test dose of 5 mg/kg (by slow IV infusion during the last hour of a dialysis session) in patients with clinical signs and symptoms of aluminum toxicity, with serum aluminum concentrations of 60–200 mcg/L, or prior to parathyroidectomy if patient has had aluminum exposure for ≥4 months.201 Test is positive for aluminum toxicity if the increase in serum aluminum above baseline is ≥50 mcg/L 2 days later at the start of the next dialysis session.201


If baseline serum aluminum concentration is >200 mcg/L, institute measures (i.e., discontinue all aluminum intake, perform dialysis 6 days per week) to reduce aluminum concentration to <200 mcg/L (to reduce risk of neurotoxicity) prior to administering deferoxamine test dose.201


Treatment in Patients with CKD

IV

Deferoxamine treatment is indicated in symptomatic patients with serum aluminum concentrations >60 but <200 mcg/L or with an increase in serum aluminum concentration of ≥50 mcg/L following deferoxamine test dose.201 To avoid deferoxamine-induced neurotoxicity in patients with serum aluminum concentrations >200 mcg/L, delay initiation of deferoxamine therapy until predialysis serum aluminum concentration is reduced to <200 mcg/L (e.g., by intensive dialysis [6 days per week with high-flux membrane; dialysate aluminum concentration <5 mcg/L], elimination of other sources of aluminum intake).201


Deferoxamine treatment considered optional in asymptomatic children receiving maintenance hemodialysis with serum aluminum concentrations of 60–200 mcg/L unless desired serum aluminum concentration is not achieved with discontinuance of aluminum-containing gels and intensive dialysis.201


Treatment recommendations are based on results of deferoxamine diagnostic testing (see table 1).















Table 1.

Deferoxamine Test Results



Deferoxamine Treatment Regimen



Occurrence of adverse neurologic effects or an increase in serum aluminum concentration of ≥300 mcg/L above baseline:



5 mg/kg infused over 1 hour once weekly for 4 months;201 administer the weekly dose 5 hours prior to high-efficiency hemodialysis to ensure rapid removal of aluminum-chelator complex201



 



Following 4 months of therapy, discontinue deferoxamine, repeat the diagnostic test dose of deferoxamine following a 1-month washout period, and assess test results201



No adverse neurologic effects and an increase in serum aluminum concentration of 50–299 mcg/L above baseline:



5 mg/kg once weekly for 2 months;201 infuse the weekly dose over the last hour of a hemodialysis session; perform high-efficiency hemodialysis 44 hours later201



 



Following 2 months of therapy, discontinue deferoxamine, repeat the diagnostic test dose of deferoxamine following a 1-month washout period, and assess test results201



No adverse neurologic effects and an increase in serum aluminum concentration of <50 mcg/L above baseline:



Repeat diagnostic test dose of deferoxamine in 1 month and (if same result obtained) again after 4 months;201 if serum aluminum concentration remains <50 mcg/L above baseline, no further therapy required201


Adults


Acute Iron Intoxication

IV or IM

Optimal dosage and duration of therapy not established.202 203 204 205 Consultation with poison control expert recommended in severe intoxications.204 205


Manufacturer recommends 1 g initially; may be followed by 500 mg every 4 hours for 2 doses.118 b Subsequent doses of 500 mg may be administered every 4–12 hours depending on clinical response (maximum 6 g in 24 hours).118 b


Chronic Iron Overload

IM

Usual IM dosage is 0.5–1 g daily.118 b In addition, administer 2 g of the drug by slow IV infusion with, but separate from, each unit of blood transfused (not to exceed 6 g with transfusion, even if ≥3 units of blood or packed RBCs transfused).118


Sub-Q

Usual dosage is 1–2 g (20–40 mg/kg) infused daily.118 b


Aluminum Toxicity

Diagnosis in Patients with CKD

IV

Test dose of 5 mg/kg (by slow IV infusion during the last hour of a dialysis session) in patients with clinical signs and symptoms of aluminum toxicity, with serum aluminum concentrations of 60–200 mcg/L, or prior to parathyroid surgery if patient has had aluminum exposure.200 Test is positive for aluminum toxicity if the increase in serum aluminum above baseline is ≥50 mcg/L 2 days later at the start of the next dialysis session.200


If baseline serum aluminum concentration is >200 mcg/L, institute measures (i.e., discontinue all aluminum intake, perform dialysis 6 days per week) to reduce aluminum concentration to <200 mcg/L (to reduce risk of neurotoxicity) prior to administering deferoxamine test dose.200


Treatment in Patients with CKD

IV

Deferoxamine treatment is indicated in symptomatic patients with serum aluminum concentrations >60 but <200 mcg/L or with an increase in serum aluminum concentration of ≥50 mcg/L following deferoxamine test dose.200 To avoid deferoxamine-induced neurotoxicity in patients with serum aluminum concentrations >200 mcg/L, delay initiation of deferoxamine therapy until predialysis serum aluminum concentration is reduced to <200 mcg/L (e.g., by intensive dialysis [6 days per week with high-flux membrane; dialysate aluminum concentration <5 mcg/L], elimination of other sources of aluminum intake).200


Treatment recommendations are based on results of deferoxamine diagnostic testing (see table 2).















Table 2.

Deferoxamine Test Results



Deferoxamine Treatment Regimen



Occurrence of adverse neurologic effects or an increase in serum aluminum concentration of ≥300 mcg/L above baseline:



5 mg/kg infused over 1 hour once weekly for 4 months;200 administer the weekly dose 5 hours prior to high-efficiency hemodialysis to ensure rapid removal of aluminum-chelator complex200



Following 4 months of therapy, discontinue deferoxamine, repeat the diagnostic test dose of deferoxamine following a 1-month washout period, and assess test results200



No adverse neurologic effects and an increase in serum aluminum concentration of 50–299 mcg/L above baseline:



5 mg/kg once weekly for 2 months;200 infuse the weekly dose over the last hour of a hemodialysis session; perform high-efficiency hemodialysis 44 hours later200



Following 2 months of therapy, discontinue deferoxamine, repeat the diagnostic test dose of deferoxamine following a 1-month washout period, and assess test results200



No adverse neurologic effects and an increase in serum aluminum concentration of <50 mcg/L above baseline:



Repeat diagnostic test dose of deferoxamine in 1 month and (if same result obtained) again after 4 months;200 if serum aluminum concentration remains <50 mcg/L above baseline, no further therapy required200


Prescribing Limits


Pediatric Patients


Acute Iron Intoxication

IV or IM

Maximum 6 g daily recommended by manufacturer.118 Some experts state that larger dosages may be required in severe intoxications.202 203 204


Chronic Iron Overload

IM

Maximum 1 g daily in the absence of transfusion, or 6 g daily with transfusion (even if ≥3 units of blood or packed RBCs transfused).118


Adults


Acute Iron Intoxication

IV or IM

Maximum 6 g daily recommended by manufacturer.118 Some experts state that larger dosages may be required in severe intoxications.202 203 204


Chronic Iron Overload

IM

Maximum 1 g daily in the absence of transfusion, or 6 g daily with transfusion (even if ≥3 units of blood or packed RBCs transfused).118


Special Populations


Hepatic Impairment


No specific dosage recommendations at this time.118


Renal Impairment


No specific dosage recommendations at this time.118 (See Renal Impairment under Cautions.)


Geriatric Patients


Select dosage with caution because of age-related decreases in renal, hepatic, and/or cardiac function and concomitant disease and drug therapy.118


Cautions for Desferal


Contraindications



  • Severe renal disease or anuria118 b (although may be used for diagnosis119 127 195 196 200 201 or treatment of aluminum toxicity in patients with chronic renal failure undergoing dialysis [see Renal Impairment under Cautions]).104 105 106 107 108 109 126 195 196 197 200 201



Warnings/Precautions


Warnings


Ocular and Otic Effects

Risk of ocular toxicity including cataracts following prolonged administration;118 b decreased visual acuity (i.e., blurred vision, visual loss);112 116 118 119 120 133 visual field defects (e.g., scotoma, loss of central or peripheral vision);112 114 115 116 118 133 160 impaired color and night vision;112 114 115 116 118 119 120 133 160 161 optic neuritis;115 116 118 133 corneal opacities;118 and retinal pigmentary abnormalities.112 115 116 118 133 160


Risk of ototoxicity including tinnitus,118 hearing loss (e.g., high frequency sensorineural hearing loss),116 117 118 160 162 audiogram abnormalities (with or without clinical hearing loss), and occasionally deafness.116 117 118 120 133 159 160 162


High dosages, prolonged therapy, and/or low iron stores increase risk for development of ocular toxicity118 159 160 161 and ototoxicity.118 159 162 164


Early detection of abnormalities important to minimize risk of irreversible toxicity.118 b Monitor patients regularly for body iron burden and hemoglobin.162 b Periodic ophthalmologic examinations (e.g., visual acuity tests, slit-lamp examinations, funduscopy) and auditory testing (e.g., otolaryngologic and audiometric examinations) recommended in patients receiving prolonged therapy.118 162 b Some clinicians recommend complete ophthalmologic examinations, studies of visual evoked potentials, and audiometry every 3 months in patients treated for chronic iron overload, particularly when dosages >50 mg/kg daily are employed.116


Immediate discontinuance of deferoxamine generally results in reversal of ocular and otic effects.118 Ocular and otic effects may partially or completely resolve following discontinuance of the drug.116 117 In some cases, ocular and otic effects may persist.112 113 114 115 116 120 133 159 If hearing loss persists, a hearing aid may be necessary.116 159 Deferoxamine therapy usually can be resumed, if necessary, at a reduced dosage with close electroretinographic monitoring.133


Effects on Bone Development and Growth

Risk of growth retardation in children receiving long-term deferoxamine therapy if excessive dosage is given or therapy is initiated prior to accumulation of a clinically important iron load.118 133 178 179 183 185 (See Pediatric Use under Cautions.)


Changes may include abnormalities in metaphyseal growth plate,118 183 185 vertebral abnormalities,133 181 182 185 and rickets- or scurvy-like changes in long bones.133 184


Growth velocity may partially return to pretreatment rates following dosage reduction.118 133 186


Adult Respiratory Distress Syndrome (ARDS)

Risk of ARDS-like condition (sometimes fatal) with dyspnea, cyanosis, and/or interstitial infiltrates.118 133 159 165 170 171 172 173


Reported in both adult and pediatric patients118 133 159 165 170 171 172 173 receiving excessively high dosages (including total and cumulative doses) and prolonged continuous IV therapy (>24 hours).118 133 159 165 167 173 202 203


Sensitivity Reactions


Hypersensitivity Reactions

Generalized rash, urticaria, angioedema, and anaphylactic reaction (with or without shock) reported.118 Local injection site reactions may be accompanied by systemic allergic reactions.118


Following rapid IV injection, flushing of the skin, generalized erythema, urticaria, hypotension, and shock may occur;118 b administer IM or by slow IV or sub-Q infusion to avoid these reactions.118 b (See IV Administration: Rate of Administration, under Dosage and Administration).


Allergic-type reactions, such as cutaneous wheal formation, pruritus, rash, and anaphylactoid reactions, reported in patients receiving long-term therapy for chronic iron overload.b


General Precautions


Susceptibility to Infection

Increased susceptibility to Yersinia enterocolitica and Y. pseudotuberculosis infections reported, potentially resulting in generalized infections.118 b


If Y. enterocolitica or Y. pseudotuberculosis infection is confirmed or strongly suspected, discontinue the drug until the infection resolves118 b and initiate appropriate anti-infective therapy.b


Fungal infections (e.g., mucormycosis, including infections caused by Rhizopus) reported rarely (sometimes fatal).118 200 201 b


If signs or symptoms suggestive of mucormycosis occur, discontinue the drug, perform mycologic tests, and initiate appropriate anti-infective therapy.118 b


Cardiovascular Effects

Hypotension, with associated tachycardia, reported following rapid IV administration of relatively large dosages.118 159 160 174 177


BP usually returns to normal ≤1 hour following discontinuance of the infusion.160


If hypotension occurs, discontinue deferoxamine and reinitiate at a slower infusion rate once BP returns to normal; however, exercise caution in attributing the hypotension to the drug in acute iron intoxication, especially when drug therapy is considered urgent.160


Increased risk of impaired cardiovascular function in patients with severe chronic iron overload receiving deferoxamine and high dosages of ascorbic acid.118 (See Interactions.)


Neurologic Effects

Potential for exacerbation of neurologic dysfunction including seizures in patients with aluminum-related encephalopathy, probably due to an acute increase in circulating aluminum.118 Risk of acute, potentially fatal neurotoxicity in those with serum aluminum concentrations >200 mcg/L; delay initiation of deferoxamine until predialysis serum aluminum concentrations are reduced to <200 mcg/L by other means (see Aluminum Toxicity, under Pediatric Patients and also under Adults, in Dosage and Administration).200 201


May precipitate the onset of dialysis dementia.118


Hypocalcemia

Treatment with deferoxamine in the presence of aluminum overload may result in decreased serum calcium concentrations and aggravate hyperparathyroidism.118


Pyelonephritis

Urinary excretion of parenterally administered iron has been reported to exacerbate latent pyelonephritis; this also may occur with deferoxamine therapy.b Use deferoxamine with caution in patients with pyelonephritis.b


Specific Populations


Pregnancy

Category C.118 b


Lactation

Not known whether deferoxamine is distributed into milk.118 Use caution in nursing women.118


Pediatric Use

Safety and efficacy not established in children <3 years of age.118


Iron mobilization with deferoxamine is relatively poor in children <3 years of age with relatively little iron overload; drug should generally not be given to such patients unless mobilization of ≥1 mg of iron daily can be demonstrated.118


Monitor growth and body weight of children receiving long-term therapy (e.g., those with thalassemia) every 3 months, since growth retardation reported; document measurements on charts to detect early changes in growth patterns and establish appropriate plan for further treatment.118 133 181


Geriatric Use

Insufficient experience in patients ≥65 years of age to determine whether geriatric patients respond differently than younger adults; select dosage with caution.118


Postmarketing experience suggests possible increased risk of ocular disorders (color blindness, maculopathy, scotoma) and ototoxicity (deafness, hearing loss) in geriatric patients.118 Unclear whether ocular disorders were dose related.118


Renal Impairment

Manufacturer states that deferoxamine is contraindicated in severe renal disease or anuria, since deferoxamine and ferrioxamine are excreted principally in urine;118 b however, may be used for diagnosis119 127 195 196 200 201 or treatment of aluminum toxicity in patients with chronic renal failure undergoing dialysis.104 105 106 107 108 109 126 195 196 197 200 201


When used for treatment of aluminum toxicity, use in a manner that maximizes removal of chelated aluminum and iron (e.g., 3 or 4 dialysis sessions scheduled between doses, appropriate intervals between deferoxamine administration and next dialysis session, use of highly permeable dialyzer membrane) (see Aluminum Toxicity, under Pediatric Patients and also under Adults, in Dosage and Administration).200 201


Common Adverse Effects


Data regarding frequency of adverse events are lacking.118


Localized pain, irritation, burning, swelling, and induration may occur at the injection site following IV or sub-Q administration.118 b


Adverse ocular and otic effects (see Warnings), abdominal discomfort, diarrhea, nausea, vomiting, leg cramps, tachycardia, and fever reported.b


Interactions for Desferal


Specific Drugs and Laboratory Tests















Drug or Test



Interaction



Comments



Ascorbic acid



Increases availability of iron for chelation118


Potential for impaired cardiovascular function following concomitant therapy with deferoxamine and high dosages of ascorbic acid (i.e., >500 mg daily in adults) in patients with severe chronic iron overload; cardiovascular dysfunction reversible following discontinuance of ascorbic acid118 b



Avoid ascorbic acid supplements in deferoxamine-treated patients with cardiac failure118


If concomitant therapy is warranted, initiate ascorbic acid only following 1 month of regular deferoxamine therapy; avoid ascorbic acid dosages of >200 mg daily (given in divided doses) in adults; in children <10 years of age, ascorbic acid 50 mg daily is recommended; for children ≥10 years of age, 100 mg daily is recommended118


Clinical monitoring of cardiac function advised in patients receiving concomitant therapy118



Prochlorperazine



Possible synergistic increase in adverse neurologic effects of the drugs; potential for temporary loss of consciousness 118 188



Gallium Ga 67



Imaging results may be distorted because of rapid urinary excretion of deferoxamine-bound gallium Ga 67118 189 190 191



Discontinuance of deferoxamine 48 hours prior to scintigraphy is advised118


Desferal Pharmacokinetics


Absorption


Bioavailability


Poorly absorbed from the GI tract in the presence of intact mucosa; however, absorption may occur in patients with acute iron intoxication.b


Distribution


Extent


Widely distributed into body tissues and fluids.b


Elimination


Metabolism


Metabolized principally by plasma enzymes, but exact pathways remain to be determined.118


Elimination Route


Excreted principally in urine as unchanged drug and ferrioxamine (gives urine a characteristic reddish color);118 b ferrioxamine also excreted in feces via bile.118


Deferoxamine is removed by dialysis.118 195 Deferoxamine-iron and deferoxamine-aluminum chelates also removed by dialysis (see Renal Impairment under Cautions).195 200 201 b


Half-life


20 minutes.198 199


Stability


Storage


Parenteral


Powder for Injection

≤25°C.118 b


Reconstituted solution is stable for 1 week at room temperature.b However, the manufacturer recommends use within 3 hours of reconstitution for microbiologic safety.118 b


Store solutions prepared under aseptic conditions for ≤24 hours at room temperature; avoid refrigeration.118 b Do not use turbid solutions.118 b


Compatibility


For information on systemic interactions resulting from concomitant use, see Interactions.


Parenteral


Solution Compatibility






Compatible118 b



Dextrose 5% in water



Ringer's injection, lactated



Sodium chloride 0.45 or 0.9%


ActionsActions



  • Chelates iron by binding ferric ions to the 3 hydroxamic groups of the molecule and forming a stable complex, ferrioxamine, that prevents iron from entering into further chemical reactions.118 b




  • A hexadentate ligand with high binding affinity for iron in a 1:1 ratio.198




  • Theoretically, 1 g of deferoxamine mesylate is capable of sequestering 85 mg of iron (as the ferric ion);118 b however, the rate of complex formation appears to be pH dependent (most rapid at acid pH).b




  • Main effect is probably on loosely bound stored iron; in vitro studies have shown that deferoxamine removes iron from ferritin, hemosiderin, and, to a lesser extent, transferrin, but not from cytochromes or hemoglobin.b




  • Also chelates aluminum104 105 106 107 108 109 and increases its excretion by the kidneys106 and/or removal by dialysis.104 105 106 107 108 109



Advice to Patients



  • Potential for drug to cause nervous system effects (e.g., dizziness) or impairment of vision or hearing; avoid driving or operating machinery if such effects occur.118




  • Advise patients that therapy may cause a reddish discoloration of urine.118




  • Importance of compliance with long-term chelation therapy for chronic iron overload.129 130 133




  • Importance of periodic ophthalmologic examinations and auditory testing during long-term therapy.118 162 b




  • Importance of informing clinicians of existing or contemplated concomitant therapy, including prescription and OTC drugs and dietary (e.g., vitamin C) and herbal supplements, as well as any concomitant illnesses.118




  • Importance of women informing their clinicians if they are or plan to become pregnant or plan to breast-feed.118




  • Importance of informing patients of other important precautionary information.118 (See Cautions.)



Preparations


Excipients in commercially available drug preparations may have clinically important effects in some individuals; consult specific product labeling for details.


















Deferoxamine Mesylate

Routes



Dosage Forms



Strengths



Brand Names



Manufacturer



Parenteral



For injection



500 mg and 2 g



Deferoxamine Mesylate for Injection



Desferal



Novartis



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This report on medications is for your information only, and is not considered individual patient advice. Because of the changing nature of drug information, please consult your physician or pharmacist about specific clinical use.


The American Society of Health-System Pharmacists, Inc. and Drugs.com represent that the information provided hereunder was formulated with a reasonable standard of care, and in conformity with p

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