This medication is used to treat high levels of a certain important body chemical (homocysteine) due to an inherited disorder (homocystinuria). Decreasing high homocysteine levels may help prevent serious blood clots, abnormal bone formation, brittle bones (osteoporosis), and eye problems (such as dislocated eye lens, nearsightedness). This medication works by decreasing blood levels of homocysteine. It does not correct the inherited disorder that causes the disease.

Take this medication by mouth as directed by your doctor, usually twice daily. Shake the bottle lightly before each use. Using the scoop provided, measure out the number of scoops prescribed by your doctor. Mix the powder with 4 to 6 ounces (120 to 180 milliliters) of water, juice, milk, or formula until dissolved, and drink immediately. The powder may also be mixed with food instead of liquid and taken immediately. Replace cap tightly after use.

The dosage is based on your age, weight, medical condition, and response to treatment. Use this medication regularly to get the most benefit from it. To help you remember, take it at the same times each day.

Tell your doctor if your condition lasts or gets worse.

Nausea, stomach upset, or diarrhea may occur. If any of these effects last or get worse, tell your doctor or pharmacist promptly.

Remember that this medication has been prescribed because your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

Tell your doctor right away if you have any serious side effects, including:

• headache that doesn't go away
• vision changes

A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including:

• rash
• itching/swelling (especially of the face/tongue/throat)
• severe dizziness
• trouble breathing

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US - Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.

In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

Before taking betaine, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

Before using this medication, tell your doctor or pharmacist your medical history, especially of:

• high methionine levels (hypermethioninemia)

During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor.

It is unknown if this medication passes into breast milk. Consult your doctor before breastfeeding.

Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.

If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call 1-800-222-1222. Canada residents can call 1-844-764-7669.

Do not share this medication with others.

Lab and/or medical tests (such as methionine/homocysteine blood levels) may be done while you are taking this medication. Keep all medical and lab appointments. Consult your doctor for more details.

If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose. Take your next dose at the regular time. Do not double the dose to catch up.

Store at room temperature away from light and moisture. Do not store in the bathroom. Keep all medications away from children and pets.

Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.