albendazole 200 mg tablet generic albenza

Uses

Cestode (Tapeworm) Infections

Albendazole is used in the treatment of tissue infections caused by the larval forms of certain cestodes (tapeworms) including neurocysticercosis caused by Cysticercus cellulosae, the larval form of Taenia solium (pork tapeworm). Albendazole also is used for the treatment of hydatid disease caused by the larval form of Echinococcus granulosus (dog tapeworm). Other anthelmintics (usually praziquantel or nitazoxanide) are used for the treatment of intestinal infections caused by adult forms of cestodes.

Neurocysticercosis

Albendazole is used for the treatment of parenchymal neurocysticercosis resulting from active lesions caused by Cysticercus cellulosae, the larval form of Taenia solium (pork tapeworm). Symptoms commonly associated with neurocysticercosis include headaches, seizures, or other CNS effects thought to result from expanding active cysticercal lesions or edema surrounding individual degenerating cysts in brain parenchyma. Therefore, important measures of response to antineurocysticercal therapy include resolution of CNS symptoms and radiologic response.

Safety and efficacy of albendazole in patients with neurocysticercosis caused by T. solium initially were demonstrated by analysis of 3 sets of data, including a compilation of data from published reports of albendazole use in neurocysticercosis, data from US compassionate use patients, and data from a limited clinical study. Analysis of 2 of the data sets combined (the report compilation and the US compassionate use data) indicated that about 41% of patients experienced a cure (no symptoms of neurocysticercosis), about 50% were considered to be improved, and 9% experienced no change. Only limited data are available from well-designed, placebo-controlled studies regarding the long-term effects of albendazole on resolution of neurocysticercosis-associated seizures. Corticosteroid and anticonvulsant therapy may be indicated prior to and/or during albendazole treatment. Concomitant corticosteroids may alleviate some adverse CNS effects resulting from albendazole-induced death of parasites within the brain.(See Precautions Related to Neurocysticercosis under Cautions: Warnings/Precautions.)

Initial treatment of parenchymal disease with seizures focuses on symptomatic treatment with anticonvulsants. Recommended antiparasitic treatment usually is albendazole, but a regimen of albendazole and praziquantel may be recommended depending on the number of viable parenchymal cysticerci. Obstructive hydrocephalus is treated with surgical removal of the obstructing cyst or CSF diversion and prednisone; arachnoiditis, vasculitis, or cerebral edema is treated with corticosteroids (prednisone or dexamethasone) used in conjunction with albendazole or praziquantel. Even when corticosteroids are used, any cysticercocidal drug may cause irreparable damage when used to treat ocular or spinal cysts; therefore, ophthalmic exams should be performed before treatment to rule out intraocular cysts.

Diagnosis and management of neurocysticercosis is complex and specialized references and experts should be consulted.

Hydatid Disease

Albendazole is used for the treatment of cystic hydatid disease (unilocular hydatid disease) of the liver, lung, and peritoneum caused by the larval form of the dog tapeworm (Echinococcus granulosus).

Surgery often is considered the treatment of choice for hydatid disease, when medically feasible, but perioperative administration of an anthelmintic drug (e.g., albendazole, mebendazole, praziquantel) may be indicated in patients undergoing surgical removal of cysts to minimize the risk of intraoperative dissemination of daughter cysts. Percutaneous drainage with ultrasound guidance plus albendazole treatment has been effective for the management of hepatic hydatid cyst disease.

Albendazole is absorbed to a greater extent, and achieves higher plasma concentrations (as its active metabolite) than mebendazole, and some clinicians consider albendazole to be a drug of choice for treatment of hydatid cyst disease caused by E. granulosus. Risks associated with surgery include operative morbidity, cyst recurrence, and anaphylaxis or dissemination of infection resulting from spillage of fluid from the cysts. Preoperative administration of albendazole may inactivate protoscolices and minimize the possibility of recurring cysts, and postoperative treatment with the drug may prevent secondary dissemination of the cestode that can occur after spontaneous or operative rupture and spillage of cyst contents. Optimal cysticidal effect of albendazole is achieved preoperatively or postoperatively when the drug is administered in three 28-day courses of therapy. Also, some clinicians have recommended administration of albendazole in patients with inoperable, widespread, or numerous E. granulosus cysts and in patients with complex medical problems who are not eligible for surgery.

Because of the low incidence of hydatid disease, safety and efficacy of albendazole in patients with hydatid disease caused by E. granulosus were demonstrated by combining data from accumulated clinical reports in small series of patients. Four sets of data were considered, including data from European compassionate use patients, an analysis of data from published studies, data from Australian compassionate use patients (not evaluable), and data from US compassionate use patients. About 30-31% of evaluable patients with hydatid disease receiving albendazole experienced a clinical cure (i.e., disappearance of cysts), and improvement (i.e., a reduction in cyst diameter of at least 25%) was observed in about 40-42% of evaluable patients. About 24% of patients receiving albendazole experienced no change or were considered to be worse.

Although albendazole has been used to treat alveolar hydatid disease, another form of hydatid cyst disease caused by Echinococcus multilocularis, surgical excision of the larval mass is the recommended and only reliable treatment for this infection. Long-term (months to years) albendazole treatment reportedly has been associated with clinical stability in some nonresectable cases and may rarely cure the infection.

Nematode (Roundworm) Infections

Ascariasis

Albendazole is used for the treatment of ascariasis caused by Ascaris lumbricoides. Albendazole, ivermectin, and mebendazole are considered the drugs of choice for the treatment of ascariasis.

Baylisascariasis

Albendazole has been used with or without corticosteroids for the treatment of baylisascariasis caused by Baylisascaris procyonis and is considered the drug of choice for the treatment of such infections.B. procyonis, a common roundworm found in the small intestine of raccoons, can cause severe or fatal encephalitis (neural larva migrans) in birds and mammals (including humans) and also can cause ocular and visceral larva migrans in humans. Humans become infected by ingesting B. procyonis eggs after contact with infected raccoon feces; young children are at particular risk for infection if they place fecally contaminated objects or fingers into their mouths. From 1973-2010, there were 22 documented cases of baylisascariasis in the US. Between May 2013 and December 2015, 6 cases of Baylisascaris neural larva migrans and 1 case of Baylisascaris ocular larva migrans were reported in the US (California, Massachusetts, Minnesota, Ohio, Oklahoma, Virginia).

Because CNS damage can occur before the patient exhibits symptoms of baylisascariasis, treatment with anthelmintic or anti-inflammatory agents initiated after symptom onset may not improve outcome. Use of an anthelmintic agent started within 1-3 days of possible infection might prevent clinical disease by killing larvae before they enter the CNS. Therefore, CDC and other clinicians recommend that albendazole treatment (with or without a corticosteroid) be initiated as soon as possible in all probable or suspected cases of baylisascariasis (e.g., CNS disease with CSF eosinophilia and likely exposure) and that preemptive treatment with albendazole be initiated immediately following a known or suspected exposure to B. procyonis (e.g., ingestion of raccoon feces, oral exposure to soil or objects contaminated with raccoon feces, playing or working near raccoon latrines) while further diagnostic investigations are being conducted. Concomitant corticosteroid therapy usually is recommended and has been used in most reported cases of baylisascariasis. If albendazole is unavailable, some clinicians suggest that mebendazole, levamisole (not commercially available in the US), or ivermectin could be tried. Ocular baylisascariasis has been treated successfully using laser photocoagulation therapy to destroy the intraretinal larvae.

Information on prevention, diagnosis, and treatment of baylisascariasis is available from the CDC at https://www.cdc.gov/parasites/baylisascaris/index.html.

Capillariasis

Albendazole has been used in the treatment of capillariasis caused by Capillaria philippinensis (Philippine threadworm). Mebendazole is considered the drug of choice for the treatment of capillariasis and albendazole is an alternative.

Enterobiasis

Albendazole is used for the treatment of enterobiasis caused by Enterobius vermicularis (pinworm). Albendazole, mebendazole, and pyrantel pamoate are considered the drugs of choice for the treatment of enterobiasis.

Filariasis

Wuchereria and Brugia Infections

Although diethylcarbamazine (available in the US from the CDC) is considered the drug of choice for the treatment of filariasis caused by Wuchereria bancrofti or Brugia malayi, ivermectin has been used (with or without albendazole) for the treatment of these infections. There is some evidence that a combined regimen of a single dose of albendazole with a single dose of diethylcarbamazine or ivermectin is more effective than any one drug alone for suppression of microfilaremia caused by W. bancrofti or B. malayi. A regimen of albendazole and ivermectin has been used effectively in patients coinfected with W. bancrofti and O. volvulus.

Loiasis

Albendazole has been used to reduce microfilaremia in the treatment of loiasis caused by Loa loa. Diethylcarbamazine (available in the US from the CDC) usually is considered the drug of choice for Loa loa infections. Albendazole may be useful for treatment of loiasis when diethylcarbamazine is ineffective or cannot be used, but repeated courses may be necessary. Because rapid killing of microfilariae may provoke encephalopathy, albendazole may be the preferred alternative (rather than ivermectin) because of its slower onset of action and decreased risk of encephalopathy.

Gnathostomiasis

For the treatment of gnathostomiasis caused by Gnathostoma spinigerum, use of albendazole or ivermectin (with or without surgical removal) is recommended.

Gongylonemiasis

For the treatment of gongylonemiasis caused by Gongylonema, surgical removal or use of albendazole is recommended.

Hookworm Infections

Cutaneous Larva Migrans

Albendazole is used for the treatment of cutaneous larva migrans (creeping eruption) caused by dog and cat hookworms. Although cutaneous larva migrans usually is self-limited with spontaneous cure after several weeks or months, albendazole or ivermectin are considered the drugs of choice when treatment is indicated.

Intestinal Hookworm Infections

Albendazole is used for the treatment of intestinal hookworm infections caused by Ancylostoma duodenale or Necator americanus, and albendazole, mebendazole, or pyrantel pamoate are considered the drugs of choice for intestinal hookworm infections.

Albendazole, mebendazole, or endoscopic removal of worms is recommended for the treatment of eosinophilic enterocolitis caused by Ancylostoma caninum (dog hookworm).

Oesophagostomiasis

Albendazole or pyrantel pamoate may be effective for the treatment of oesophagostomiasis caused by Oesophagostomum bifurcum.

Strongyloidiasis

Albendazole is used for the treatment of strongyloidiasis caused by Strongyloides stercoralis (threadworm). Some clinicians consider ivermectin the drug of choice and albendazole an alternative for the treatment of strongyloidiasis. Prolonged or repeated treatment may be necessary in people with hyperinfection and disseminated strongyloidiasis, and relapse can occur.

Toxocariasis (Visceral Larva Migrans)

Albendazole is used for the treatment of toxocariasis (visceral larva migrans) caused by Toxocara canis or T. cati (dog or cat roundworms), and albendazole or mebendazole are considered the drugs of choice for these infections. In severe cases with cardiac, ocular, or CNS involvement, corticosteroids also may be indicated. Treatment may not be effective in ocular larva migrans; inflammation may be reduced by corticosteroid injections and surgery may be necessary for secondary damage.

Trichinellosis

Albendazole is used for the treatment of trichinellosis (trichinosis) caused by Trichinella spiralis (pork worm). Although some clinicians state that albendazole and mebendazole are equally effective for the treatment of trichinellosis, other clinicians consider albendazole the drug of choice and mebendazole the alternative agent. Use of corticosteroids in addition to the anthelmintic usually is recommended, especially when symptoms are severe. Corticosteroids alleviate symptoms of the inflammatory reaction and can be lifesaving when cardiac or CNS systems are involved.

Trichostrongyliasis

Albendazole is used in the treatment of trichostrongyliasis. Pyrantel pamoate is considered the drug of choice for the treatment of Trichostrongylus infections and albendazole and mebendazole are alternatives.

Trichuriasis

Albendazole is used in the treatment of trichuriasis caused by Trichuris trichiura (whipworm). Albendazole is considered the drug of choice and mebendazole and ivermectin are alternatives for the treatment of trichuriasis.

Trematode (Fluke) Infections

For the treatment of infections caused by Clonorchis sinensis (Chinese liver fluke) or Opisthorchis viverrini (Southeast Asian liver fluke), albendazole and praziquantel are recommended as the drugs of choice. Other anthelmintics (usually praziquantel) are recommended for all other fluke infections.

Giardiasis

Although metronidazole, tinidazole, or nitazoxanide generally are considered the drugs of choice for the treatment of giardiasis caused by Giardia duodenalis (also known as G. lamblia or G. intestinalis), albendazole may be an alternative for the treatment of giardiasis.

Microsporidiosis

Albendazole has been used in the treatment of microsporidiosis. Microsporidia can cause ocular infections (e.g., Encephalitozoon hellem, E. cuniculi, Vittaforma corneae), intestinal infections (e.g., Enterocytozoon bieneusi, E. intestinalis), and disseminated infections (e.g., E. hellem, E. cuniculi, E. intestinalis, Pleistophora, Trachipleistophora, Brachiola vesicularum). Intestinal infections are most common in immunocompromised patients, including patients with human immunodeficiency virus (HIV) infection (especially those with CD4 T-cell counts less than 100 cells/mm) and organ transplant recipients.

Ocular infections caused by microsporidia usually are treated with albendazole in conjunction with topical ophthalmic fumagillin (not commercially available in the US). While topical fumagillin may clear susceptible microsporidia from the eye, albendazole is used to clear microsporidia that persist systemically. Topical fumagillin therapy generally is not effective for ocular lesions caused by V. corneae, and keratoplasty may be necessary.

For the treatment of intestinal infections caused by E. intestinalis and disseminated infections caused by microsporidia other than E. bieneusi and V. corneae, albendazole usually is the drug of choice. Some clinicians recommend that albendazole be used in conjunction with itraconazole for the treatment of disseminated disease caused by Trachipleistophora or Anncaliia.

Albendazole is ineffective in infections caused by E. bieneusi and V. corneae, and generally is recommended for initial treatment of intestinal and disseminated microsporidiosis only when the infection is caused by microsporidia other than E. bieneusi and V. corneae.

Dosage and Administration

General

Blood cell counts should be evaluated prior to and during albendazole treatment.(See Hematologic Effects under Cautions: Warnings/Precautions.)

Hepatic enzymes (aminotransferases) should be evaluated prior to and during albendazole treatment.(See Hepatic Effects under Cautions: Warnings/Precautions.)

A pregnancy test should be performed prior to initiating albendazole in women of reproductive potential.(See Fetal/Neonatal Morbidity and Mortality under Cautions: Warnings/Precautions.)

Administration

Albendazole film-coated tablets are administered orally with food.

Oral bioavailability of albendazole appears to be increased when the drug is administered with a fatty meal. When the drug is administered with a fatty meal containing about 40 g of fat, plasma concentrations of albendazole sulfoxide (active metabolite of albendazole) are up to 5 times higher than those observed when the drug is administered to fasting patients.

In patients who have difficulty swallowing tablets whole (particularly children), albendazole tablets may be crushed or chewed and swallowed with a drink of water.

Dosage

Cestode (Tapeworm) Infections

Neurocysticercosis

For the treatment of neurocysticercosis caused by the larval form of the pork tapeworm (Taenia solium) in adults and children weighing 60 kg or more, the usual dosage of albendazole is 400 mg given twice daily with meals for 8-30 days. For the treatment of neurocysticercosis in patients weighing less than 60 kg, the usual daily dosage of albendazole is 15 mg/kg daily (not to exceed 800 mg daily), administered as 2 equally divided doses with meals, for 8-30 days. Courses of albendazole treatment may be repeated as necessary.

Concomitant corticosteroid therapy should be considered to prevent cerebral hypertensive episodes during the first week of treatment, and appropriate anticonvulsant therapy should be used if indicated.(See Precautions Related to Neurocysticercosis under Cautions: Warnings/Precautions.)

Hydatid Disease

For the treatment of cystic hydatid disease of the liver, lung, or peritoneum caused by the larval form of the dog tapeworm (Echinococcus granulosus) in adults or children weighing 60 kg or more, the usual dosage of albendazole is 400 mg twice daily given with meals for 28 days, followed by a 14-day albendazole-free interval, and this regimen is repeated for a total of 3 dosage cycles. For patients weighing less than 60 kg, the usual dosage is 15 mg/kg daily (not to exceed 800 mg daily), administered in 2 equally divided doses with meals for 28 days, followed by a 14-day albendazole-free interval, and this regimen is repeated for a total of 3 dosage cycles.

Some clinicians recommend that adults and pediatric patients receive 15 mg/kg daily (not to exceed 800 mg daily) administered in 2 equally divided doses for 1-6 months for the treatment of hydatid cyst disease.

Nematode (Roundworm) Infections

Ascariasis

For the treatment of ascariasis caused by Ascaris lumbricoides, some clinicians recommend that adult and pediatric patients receive a single 400-mg dose of albendazole.

Baylisascariasis

For the treatment of baylisascariasis caused by Baylisascaris procyonis or preemptive treatment following a suspected or confirmed exposure to B. procyonis(see Baylisascariasis under Uses: Nematode [Roundworm] Infections), the US Centers for Disease Control and Prevention (CDC) and other clinicians recommend that albendazole be given in a dosage of 20-50 mg/kg daily with or without a corticosteroid.

Treatment should be initiated immediately if baylisascariasis is probable and should not be delayed until symptoms emerge or the diagnosis is confirmed. Treatment should be continued for at least 10 days, and usually has been continued for 3-6 weeks.

Preemptive treatment should be initiated immediately following a suspected or confirmed exposure to B. procyonis, and should be continued for 10-20 days while further diagnostic investigations are conducted.

Capillariasis

For the treatment of capillariasis caused by Capillaria philippinensis (Philippine threadworm), some clinicians recommend that adults and pediatric patients receive albendazole in a dosage of 400 mg once daily for 10 days.

Enterobiasis

For the treatment of enterobiasis caused by Enterobius vermicularis (pinworm), some clinicians recommend that adult and pediatric patients receive an initial 400-mg dose of albendazole and a second 400-mg dose given 2 weeks later.

Because other family members often are infected, some clinicians recommend that all household contacts of patients with enterobiasis receive treatment, especially when multiple or repeated symptomatic infections are occurring in the household.

Gnathostomiasis

Some clinicians recommend that adults and pediatric patients with gnathostomiasis caused by Gnathostoma spinigerum receive albendazole in a dosage of 400 mg twice daily for 21 days.

Gongylonemiasis

For the treatment of gongylonemiasis caused by Gongylonema, some clinicians recommend that adults and pediatric patients receive albendazole in a dosage of 400 mg daily for 3 days.

Hookworm Infections

For the treatment of cutaneous larva migrans (creeping eruption) caused by dog or cat hookworms, some clinicians recommend that adults and pediatric patients receive albendazole in a dosage of 400 mg once daily for 3 days.

For the treatment of intestinal hookworm infections caused by Ancylostoma duodenale or Necator americanus, some clinicians recommend that adult and pediatric patients receive a single 400-mg dose of albendazole. A repeat stool examination (using a concentration technique) for eggs of A. duodenale or N. americanus should be performed 2 weeks after treatment and the regimen should be repeated if results are positive.

For the treatment of eosinophilic enterocolitis caused by Ancylostoma caninum (dog hookworm), some clinicians recommend that adult and pediatric patients receive a single 400-mg dose of albendazole.

Strongyloidiasis

For the treatment of strongyloidiasis caused by Strongyloides stercoralis (threadworm), some clinicians recommend that adults and pediatric patients receive albendazole in a dosage of 400 mg twice daily for 7 days. It may be necessary to repeat or prolong treatment or use other agents in immunocompromised individuals or those with disseminated disease.

Toxocariasis (Visceral Larva Migrans)

For the treatment of toxocariasis (visceral larva migrans) caused by dog or cat roundworms, some clinicians recommend that adults and pediatric patients receive albendazole in a dosage of 400 mg twice daily for 5 days. However, optimum duration of treatment is not known and some clinicians recommend that treatment be continued for up to 20 days.

Trichinellosis

For the treatment of trichinellosis (trichinosis) caused by Trichinella spiralis (pork worm), some clinicians recommend that adults and pediatric patients receive albendazole in a dosage of 400 mg twice daily for 8-14 days.

Trichostrongyliasis

For the treatment of infections caused by Trichostrongylus, some clinicians recommend that adults and pediatric patients receive a single 400-mg dose of albendazole.

Trichuriasis

Some clinicians recommend that adults and pediatric patients with trichuriasis caused by Trichuris trichiura (whipworm) receive albendazole in a dosage of 400 mg once daily for 3 days.

Trematode (Fluke) Infections

For the treatment of infections caused by Clonorchis sinensis (Chinese liver fluke) or Opisthorchis viverrini (Southeast Asian liver fluke), some clinicians recommend that adults and pediatric patients receive albendazole in a dosage of 10 mg/kg daily given for 7 days.

Giardiasis

For the treatment of giardiasis caused by Giardia duodenalis (also known as G. lamblia or G. intestinalis), some clinicians recommend that adults receive albendazole in a dosage of 400 mg daily for 5 days and that pediatric patients receive a dosage of 10 mg/kg daily for 5 days.

Microsporidiosis

For the treatment of ocular microsporidiosis, some clinicians recommend that adults receive albendazole in a dosage of 400 mg twice daily and that pediatric patients receive 7.5 mg/kg (up to 400 mg) twice daily in conjunction with topical ophthalmic fumagillin (not commercially available in the US). In patients with human immunodeficiency virus (HIV) infection, some experts recommend that treatment of ocular microsporidiosis be continued until ocular symptoms resolve and there has been a sustained immune response to antiretroviral therapy (CD4 T-cell count greater than 200 cells/mm for at least 6 months in adults or CDC immunologic category 1 or 2 for longer than 6 months in children).

For the treatment of intestinal or disseminated microsporidiosis caused by microsporidia other than Enterocytozoon bieneusi or Vittaforma corneae, some clinicians recommend that adults receive albendazole in a dosage of 400 mg twice daily and that pediatric patients receive 7.5 mg/kg (up to 400 mg) twice daily. Some clinicians recommend a treatment duration of 21 days in patients with intestinal infections. In HIV-infected patients with intestinal or disseminated microsporidiosis, some experts recommend that treatment be continued until symptoms resolve and there has been a sustained immune response to antiretroviral therapy (CD4 T-cell count greater than 200 cells/mm for at least 6 months in adults or CDC immunologic category 1 or 2 for longer than 6 months in children).

If albendazole is used in conjunction with itraconazole for the treatment of disseminated disease caused by Trachipleistophora or Anncaliia, some clinicians recommend that adults receive albendazole in a dosage of 400 mg twice daily.

Special Populations

No special population dosage recommendations.

Cautions

Contraindications

Albendazole is contraindicated in patients hypersensitive to benzimidazole derivatives or any component in the formulation.

Warnings/Precautions

Sensitivity Reactions

Hypersensitivity Reactions

Hypersensitivity reactions, including rash and urticaria, have been reported rarely in patients receiving albendazole. Erythema multiforme and Stevens-Johnson syndrome have been reported during postmarketing experience.

Hematologic Effects

Albendazole may cause bone marrow suppression, aplastic anemia, and agranulocytosis. Leukopenia, granulocytopenia, pancytopenia, agranulocytosis, and thrombocytopenia have been reported in less than 1% of patients receiving albendazole. Fatalities related to granulocytopenia or pancytopenia have been reported.

Blood cell counts should be evaluated at the beginning of each 28-day treatment cycle of albendazole and every 2 weeks during treatment with the drug. Patients with liver disease and those with hepatic echinococcosis are at increased risk for bone marrow suppression, and more frequent monitoring of blood cell counts is warranted in such patients.

Albendazole should be discontinued if clinically important decreases in blood cell counts occur.

Fetal/Neonatal Morbidity and Mortality

Albendazole may cause fetal harm. Teratogenic effects (embryotoxicity, skeletal malformations) have been reported in rats and rabbits.

Pregnancy should be excluded before initiating albendazole in women of reproductive potential. Women of reproductive potential should be advised to use effective birth control to avoid pregnancy during and for 1 month after completion of albendazole treatment.(See Pregnancy under Warnings/Precautions: Specific Populations, in Cautions.)

Hepatic Effects

Mild to moderate increases in hepatic enzymes have been reported in approximately 16% of patients receiving albendazole in clinical trials. Increased hepatic enzymes generally returned to normal when the drug was discontinued; however, acute liver failure of uncertain causality and hepatitis have been reported. Patients with elevated hepatic enzymes are at increased risk for hepatotoxicity. Albendazole should be discontinued if clinically important increases in hepatic enzymes occur.

Hepatic enzymes (aminotransferases) should be evaluated at the beginning of each 28-day treatment cycle of albendazole and at least every 2 weeks during treatment with the drug. If hepatic enzyme concentrations exceed twice the upper limit of normal, consideration should be given to discontinuance of the drug based on the individual patient circumstance. Decisions to reinstitute albendazole when hepatic enzymes return to pretreatment levels should be individualized taking into account the risks and benefits of further albendazole treatment. If the drug is reinstituted, laboratory tests should be performed frequently.

Precautions Related to Neurocysticercosis

Because of its activity against the pork tapeworm (Taenia solium), use of albendazole for the treatment of neurocysticercosis resulting from active lesions caused by Cysticercus cellulosae (the larval form of T. solium) has been associated with adverse CNS effects (e.g., seizures, increased intracranial pressure and focal signs, hydrocephalus) resulting from inflammatory reactions caused by albendazole-induced death of parasites within the brain.

Patients receiving albendazole for the treatment of neurocysticercosis should receive appropriate corticosteroid and anticonvulsant therapy as required. Oral or IV corticosteroid therapy should be considered during the first week of albendazole treatment to prevent cerebral hypertensive episodes.

Patients with neurocysticercosis may have retinal lesions, and destruction of cysticercal lesions by albendazole may cause retinal damage. Therefore, patients should be examined for the presence of retinal lesions and, if such lesions are present, the need for treatment of neurocysticercosis should be weighed against the possibility of retinal damage resulting from inflammatory reactions caused by albendazole-induced death of parasites in the eye.

Undiagnosed neurocysticercosis may be uncovered in patients receiving albendazole treatment for other conditions. Before initiating albendazole, patients with epidemiologic factors that increase the risk for neurocysticercosis should be evaluated.

Specific Populations

Pregnancy

Albendazole may cause harm to the fetus. The drug should be used during pregnancy only if potential benefits justify the risks to the fetus and only when no alternative management is appropriate.

Albendazole should be initiated in women of childbearing age only after a negative pregnancy test. Women of childbearing potential should be advised to use effective contraceptive measures during albendazole treatment and for 1 month after treatment with the drug is discontinued. If a patient becomes pregnant while receiving albendazole, the drug should be immediately discontinued and the woman should be apprised of the potential hazard to the fetus.

Teratogenic effects (embryotoxicity, skeletal malformations) have been reported in rats and rabbits. In rats, albendazole was teratogenic at oral dosages of 10 and 30 mg/kg daily (approximately 0.1 and 0.3 times the recommended human dosage, respectively) given during gestation days 6-15. In rabbits, teratogenic effects were reported at oral dosages of 30 mg/kg daily (0.6 times the recommended human dosage) given during gestation days 7-19. Maternal toxicity (33% mortality) was reported in rabbits receiving an albendazole dosage of 30 mg/kg daily.

Lactation

Albendazole is distributed into milk in animals; distribution into human milk also has been reported.

Albendazole should be used with caution in nursing women.

Pediatric Use

Efficacy of albendazole for the treatment of neurocysticercosis in pediatric patients appears to be similar to that in adults. Hydatid disease is uncommon in infants and young children.

Albendazole pharmacokinetics in pediatric patients 6-13 years of age are similar to pharmacokinetics in adults.

Geriatric Use

Data are insufficient to determine whether safety and efficacy of albendazole for the treatment of neurocysticercosis or hydatid disease in patients 65 years of age and older differ from that in younger patients.

Albendazole pharmacokinetics in geriatric patients have not been fully evaluated, but data from adults up to 79 years of age with hydatid cysts suggest that pharmacokinetics in these patients are similar to that in younger patients.

Hepatic Impairment

Individuals with hepatic impairment are at increased risk for hepatotoxicity and bone marrow suppression during albendazole treatment. Albendazole should be discontinued if hepatic enzymes exceed twice the upper normal limit or if clinically important decreases in blood cell counts occur.

In patients with extrahepatic obstruction, systemic availability of albendazole sulfoxide (active metabolite of albendazole) was increased (i.e., twofold increase in peak serum concentration and sevenfold increase in area under the plasma concentration-time curve [AUC]). The rate of absorption and elimination of albendazole sulfoxide in these patients appeared to be prolonged with a mean time to peak serum concentrations of 10 hours and mean serum elimination half-life of 31.7 hours.

Renal Impairment

Pharmacokinetics of albendazole have not been evaluated to date in patients with impaired renal function.

Common Adverse Effects

Treatment of neurocysticercosis: Adverse effects reported in 1% or more of patients include headache, nausea, vomiting, increased intracranial pressure, and meningeal signs.

Treatment of hydatid disease: Adverse effects reported in 1% or more of patients include elevated hepatic enzymes, abdominal pain, nausea, vomiting, reversible alopecia, fever, headache, dizziness, and vertigo.

Drug Interactions

Albendazole induces cytochrome P-450 (CYP) isoenzyme 1A in human hepatoma cells.

Cimetidine

Concomitant use of albendazole (20 mg/kg daily) and cimetidine (10 mg/kg daily) in hydatid cyst patients resulted in a twofold increase in concentrations of albendazole sulfoxide (active metabolite of albendazole) in bile and cystic fluid compared with use of albendazole alone. Albendazole plasma concentrations were unchanged 4 hours after dosing.

Dexamethasone

Concomitant use of dexamethasone (8 mg) with each dose of albendazole (15 mg/kg daily) in patients with neurocysticercosis resulted in a 56% increase in steady-state trough concentrations of albendazole sulfoxide.

Praziquantel

When praziquantel (40 mg/kg) was administered concomitantly with albendazole (400 mg) in healthy individuals in the fed state, mean peak plasma concentrations and area under the plasma concentration-time curve (AUC) of albendazole sulfoxide were increased by about 50% compared with individuals who received albendazole alone; however, the mean time to peak plasma concentrations and mean plasma elimination half-life of albendazole sulfoxide were not affected. In addition, praziquantel pharmacokinetics were not affected.

Theophylline

Concomitant administration of a single dose of albendazole (400 mg) did not affect the pharmacokinetics of theophylline (aminophylline 5.8 mg/kg infused over 20 minutes). However, because albendazole induces CYP1A in human hepatoma cells, plasma concentrations of theophylline should be monitored during and after albendazole treatment.