Ethambutol is a bacteriostatic antimycobacterial drug prescribed to treat tuberculosis (Mycobacterium tuberculosis). It is usually given in combination with other tuberculosis drugs, such as isoniazid, pyrazinamide and rifampicin.

It is sold under the name "Myambutol".

Mechanism

Bacteriostatic against actively growing TB bacilli, it works by obstructing the formation of cell wall. Mycolic acids attach to the 5'-hydroxyl groups of D-arabinose residues of arabinogalactan and form mycolyl-arabinogalactan-peptidoglycan complex in the cell wall. It disrupts arabinogalactan synthesis by inhibiting the enzyme arabinosyl transferase. Disruption of the arabinogalactan synthesis inhibits the formation of this complex and leads to increased permeability of the cell wall.

Pharmacokinetics

It is well absorbed from the gastrointestinal tract and well distributed in body tissues and fluids, 50% is excreted unchanged in urine.

Side Effects

• Optic neuritis
• Red-green color blindness
• Peripheral neuropathy
• Arthralgia

External links

• Medline Plus drug information
• Prescribing Information for MYAMBUTOL