Methionine Interactions Overview

Additional Details

Is Methionine Safe? Are There Any Warnings?

Methionine is considered safe when used orally in the amounts commonly found in food. It is typically safe when used medicinally in appropriate amounts under the supervision of a healthcare professional. However, excessive doses of methionine, over 100 mg/kg, should be avoided to prevent potentially lethal cerebral effects.

It is important to use intravenous methionine cautiously in infants receiving parenteral nutrition, as high levels of methionine can cause liver toxicity in this population. There is insufficient information available regarding the safety of methionine during pregnancy and lactation, so it is best to avoid using it in medicinal doses during these times.

Adverse Effects

Methionine is generally well-tolerated. However, some common adverse effects may include dizziness, drowsiness, hypotension, irritability, and vomiting. Other possible effects include headache, increased homocysteine levels, increased urinary calcium excretion, and leukocytosis. Serious adverse effects such as cerebral edema, hepatic encephalopathy, and liver toxicity are rare but possible.

Effectiveness

Methionine is considered possibly effective for reducing the risk of neural tube birth defects when consumed in high dietary intake during pregnancy.

More evidence is needed to establish the effectiveness of methionine for other conditions such as acetaminophen poisoning, allergic rhinitis, asthma, breast cancer, cisplatin-associated ototoxicity, colorectal cancer, genital herpes, herpes zoster, human papillomavirus (HPV), menopausal symptoms, pancreatitis, Parkinson disease, urinary tract infections (UTI), wound healing, and others.

Dosing & Administration

The recommended dosages of methionine depend on the specific condition and the age group:

• Adult oral dosage: There is no specific recommended standard dosage of methionine for adults in most cases. The dosage depends on the condition being treated. It is important to follow the guidance and instructions given by a healthcare professional.
• Child oral dosage: The daily recommended dietary allowance (RDA) of methionine plus cysteine is 58 mg/kg for infants 3-4 months old, 27 mg/kg for children approximately 2 years old, and 22 mg/kg for children 10-12 years old. These guidelines are based on body weight and can vary depending on the child's individual needs.
• Adult and child intravenous (IV) dosage: The appropriate dosage of IV methionine varies depending on the specific medical condition and individual patient factors. It is essential to consult a healthcare professional for precise dosage instructions.

Pharmacokinetics and Mechanism of Action

Methionine is an essential amino acid that plays various roles in cellular function. It is involved in protein synthesis and methylation of DNA, RNA, and other molecules.

Methionine can exhibit anticancer effects by promoting apoptosis (cell death), protecting DNA, and reducing inflammation. Methionine has antioxidant properties and can stimulate basal growth hormone secretion. It also participates in glutathione synthesis, which has a hepatoprotective effect. The mechanism of methionine's action varies depending on the condition being treated. More research is needed to fully understand its pharmacokinetics.

Interactions

No known interactions with drugs, supplements, or lab tests have been identified.

Standardization & Formulation

There is insufficient information available about the standardization and specific formulations of methionine.

Drugs that interact with Methionine