Levomethadyl acetate

Levomethadyl Acetate (also known as LAAM, OrLAAM or Levo-alpha-acetylmethadol) is a synthetic opioid similar in structure to methadone. It has a long duration of action due to its active metabolites. LAAM was used in the treatment of opioid dependence but was withdrawn from the US and European markets due to concerns about life-threatening side effects.

History

Levomethadyl Acetate was first synthesized in the 1940s. It was approved by the FDA in 1993 for use in the treatment of opioid dependence. The drug was withdrawn from the market in 2003 in the US and in 2001 in Europe due to concerns about cardiac arrhythmias.

Pharmacology

Levomethadyl Acetate is a synthetic opioid and acts as an agonist at the mu-opioid receptor. It is metabolized in the liver into active metabolites nor-LAAM and dinor-LAAM, which are also agonists at the mu-opioid receptor. These metabolites are responsible for the long duration of action of LAAM, allowing for dosing every two to three days.

Side Effects

The most common side effects of Levomethadyl Acetate include nausea, vomiting, constipation, sweating, dizziness, and somnolence. Serious side effects include QT interval prolongation, which can lead to life-threatening ventricular arrhythmias.

Withdrawal

Levomethadyl Acetate was withdrawn from the market due to concerns about QT interval prolongation and ventricular arrhythmias. These concerns were based on post-marketing surveillance data. Despite its withdrawal, LAAM is still listed on the WHO List of Essential Medicines.

See Also

• Methadone
• Opioid dependence
• Opioid receptor