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Pronunciation
(BAY ta een)
Generic Available (U.S.)
No
Index Terms
Prescribing and Access Restrictions
Cystadane® may be obtained by contacting Accredo Health Group Inc at 1-888-454-8860.
Brand Names: U.S.
Brand Names: Canada
Pharmacologic Category
Use: Labeled Indications
Treatment of homocystinuria (eg, deficiencies or defects in cystathionine beta-synthase [CBS], 5,10-methylene tetrahydrofolate reductase [MTHFR], and cobalamin cofactor metabolism [CBL])
Pregnancy Risk Factor
C
Pregnancy Considerations
Animal reproduction studies have not been conducted with betaine. It is not known whether betaine can cause fetal harm when administered to a pregnant woman or can affect reproductive capacity. Betaine should be given to a pregnant woman only if needed.
Lactation
Excretion in breast milk unknown/use caution
Breast-Feeding Considerations
Betaine is found naturally in human breast milk. The influence from betaine therapy is unknown.
Contraindications
There are no contraindications listed within the manufacturer's labeling.
Warnings/Precautions
Special populations:
• Cystathionine beta-synthase (CBS) deficiency: Use caution in patients with CBS deficiency; treatment with betaine may cause large increases of plasma methionine concentrations which may cause cerebral edema.
Adverse Reactions
Frequency not defined: Gastrointestinal: Diarrhea, dysgeusia, GI distress, nausea
Postmarketing and/or case reports: Alopecia, anorexia, agitation, cerebral edema (associated with hypermethioninemia), dental disorders, depression, hives, glossitis, irritability, personality disorder, sleep disturbances, skin odor abnormalities, urinary incontinence, vomiting
Metabolism/Transport Effects
None known.
Drug Interactions
There are no known significant interactions.
Storage
Store at 15°C to 30°C (59°F to 86°F). Protect from moisture
Mechanism of Action
Betaine acts as a methyl group donor in the remethylation of homocysteine to methionine. Homocystinuria is an inborn error of metabolism in which elevated plasma homocysteine levels can lead to mental retardation, ocular abnormalities, osteoporosis, premature atherosclerosis and thromboembolic disease. Remethylation is one of the two divergent pathways in the metabolism of homocysteine. The second pathway involves transulfuration of homocysteine to produce cysteine. A number of enzymes and cofactors are also involved in these pathways.
Dosage
Oral:
Children <3 years: Initial dose: 100 mg/kg/day administered in 2 divided doses; increase weekly by 50 mg/kg increments, as needed
Children ≥3 years and Adults: Usual dose: 6 g/day administered in divided doses of 3 g twice daily; dosages of up to 20 g/day have been necessary to control homocysteine levels in some patients
Note: Dosage in all patients can be gradually increased until plasma total homocysteine is undetectable or present only in small amounts. One study in six patients with CBS deficiency, ranging from 6-17 years of age, showed minimal benefit from exceeding a twice daily dosing schedule and a 150 mg/kg/day dosage.
Administration: Oral
Measure prescribed amount with provided measuring scoop and dissolve in 120-180 mL of water, juice, milk, or formula, or mix with food for immediate ingestion.
Monitoring Parameters
Total plasma homocysteine levels to determine therapeutic response. In patients with elevated plasma methionine (eg, CBS deficiency), monitor plasma methionine (maintain <1000 micromol/L).
Dietary Considerations
May be mixed with water, juice, milk, formula, or with food. Betaine is a metabolite of choline and is present in small amounts in foods such as beets, spinach, cereals, and seafood.
Additional Information
Betaine has been used in conjunction with vitamin B6 (pyridoxine), vitamin B12 (cobalamin), and folate in the management of homocystinuria.
Dental Health: Effects on Dental Treatment
No significant effects or complications reported
Dental Health: Vasoconstrictor/Local Anesthetic Precautions
No information available to require special precautions
Mental Health: Effects on Mental Status
None reported
Mental Health: Effects on Psychiatric Treatment
None reported
Dosage Forms
Excipient information presented when available (limited, particularly for generics); consult specific product labeling.
Powder for solution, oral, as anhydrous:
Cystadane®: 1 g/scoop (180 g) [1 scoop = 1.7 mL]
References
Burns SP, Iles RA, Ryalls M, et al “Methylgenesis From Betaine in Cystathionine-Beta-Synthase Deficiency,” Biochem Soc Trans, 1993, 21:455S.
Devlin AM, Hajipour L, Gholkar A, “Cerebral Edema Associated With Betaine Treatment in Classical Homocystinuria,” J Pediatr, 2001,144(4):545-8.
Kishi T, Kawamura I, Harada Y, et al, “Effect of Betaine on S-Adenosylmethionine Levels in the Cerebrospinal Fluid in a Patient With Methylenetetrahydrofolate Reductase Deficiency and Peripheral Neuropathy,” J Inherit Metab Dis, 1994, 17:560-5.
Lawson-Yuen A and Levy, HL, “The Use of Betaine in the Treatment of Elevated Homocysteine,” Mol Genet Metab, 2006, 88(3):201-7.
Matthews A, Johnson TN, Rostami-Hodjegan A, et al, “An Indirect Response Model of Homocysteine Suppression by Betaine: Optimising the Dosage Regimen of Betaine in Homocystinuria,” Br J Clin Pharmacol, 2002, 54(2):140-6.
Smolin LA, Benevenga NJ, and Berlow S, “The Use of Betaine for the Treatment of Homocystinuria,” J Pediatr, 1981, 99:467-72.
International Brand Names
Lexi-Comp.com
Last full review/revision October 2011
Content last modified October 2011
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