Labeled Ethambutol. Antibacterial (tuberculostatic).Ethambutol (commonly abbreviated EMB or simply E) is a medication primarily used to treat tuberculosis.[2] It is usually given in combination with other tuberculosis drugs, such as isoniazid, rifampicin and pyrazinamide. It may also be used to treat Mycobacterium avium complex, and Mycobacterium kansasii.[3]It can cause problems with vision, liver problems and allergies among other side effects.[3] It is pregnancy category C in the United States due to concerns with eye issues and category A in Australia meaning that they did not find evidence of harm after being taken by many pregnant women.[3][4] It is reasonable to use during breast feeding if required.[3]It is sold under the trade names Myambutol and Servambutol. It is on the World Health Organization's List of Essential Medicines, a list of the most important medication needed in a basic health system.[5].Form:Light Beige SolidMelting Point:185-188°CSolubility:Methanol, Water