What Is Apo-Ethambutol?
Apo-Ethambutol is an antibiotic that prevents growth of the tuberculous bacteria in the body.
Apo-Ethambutol is used to treat tuberculosis (TB), and is usually given together with at least one other tuberculosis medicine.
Apo-Ethambutol may also be used for purposes not listed in this medication guide.
Apo-Ethambutol can cause serious vision problems or irreversible vision loss. You may not be able to take this medicine if you have an eye problem or vision disorder.
You should not use Apo-Ethambutol if you are allergic to it. You may not be able to take Apo-Ethambutol if you have an eye condition called optic neuritis (inflammation of nerve fibers behind your eyes). Your doctor will decide if this treatment is right for if you have an eye disorder.
Apo-Ethambutol can cause vision problems that may be a sign that you should stop taking the medicine. You may not be able to take Apo-Ethambutol if you cannot recognize or report any changes in your vision. Young children or debilitated patients may not be able to tell someone about vision problems.
To make sure Apo-Ethambutol is safe for you, tell your doctor if you have:
- inflammatory eye disorders such as uveitis or iritis;
- eye problems caused by diabetes;
- liver disease;
- kidney disease; or
FDA pregnancy category C. It is not known whether Apo-Ethambutol will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant while using this medicine.
Apo-Ethambutol can pass into breast milk and may harm a nursing baby. Tell your doctor if you are breast-feeding a baby.
Apo-Ethambutol should not be given to a child younger than 13 years old.
Toxicological studies in dogs on high prolonged doses produced evidence of myocardial damage and failure, and depigmentation of the tapetum lucidum of the eyes, the significance of which is not known. Degenerative changes in the central nervous system, apparently not dose-related, have also been noted in dogs receiving Apo-Ethambutol hydrochloride over a prolonged period. In the rhesus monkey, neurological signs appeared after treatment with high doses given daily over a period of several months. These were correlated with specific serum levels of Apo-Ethambutol and with definite neuroanatomical changes in the central nervous system. Focal interstitial carditis was also noted in monkeys which received Apo-Ethambutol hydrochloride in high doses for a prolonged period.
Apo-Ethambutol HCl is contraindicated in patients who are known to be hypersensitive to this drug. It is also contraindicated in patients with known optic neuritis unless clinical judgment determines that it may be used. Apo-Ethambutol HCl is contraindicated in patients who are unable to appreciate and report visual side effects or changes in vision (e.g., young children, unconscious patients).
What other drugs will affect Apo-Ethambutol?
Other drugs may interact with Apo-Ethambutol, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell each of your health care providers about all medicines you use now and any medicine you start or stop using.
What should I avoid while taking Apo-Ethambutol?
Avoid taking an antacid containing aluminum hydroxide (Alternagel, Maalox, Mi-Acid, Mylanta, Rulox) within 4 hours after you take Apo-Ethambutol. Some antacids can make it harder for your body to absorb Apo-Ethambutol.
How is Apo-Ethambutol Supplied
Apo-Ethambutol hydrochloride Tablets USP
100 mg – round, convex, white, film coated tablets engraved E6 on one side are supplied as follows:
NDC 54879-001-01 - Bottle of 100
400 mg – round, convex, white, scored, film coated tablets engraved with E to the left and 7 to the right of the score on one side are supplied as follows:
NDC 54879-002-01 - Bottle of 100
Store at controlled room temperature 20 ° to 25 ° C (68 ° to 77 ° F).
Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
Manufactured For & Distributed by:
Newtown, PA 18940
Subclinical Apo-Ethambutol optic neuropathy
There are methods for detecting subclinical Apo-Ethambutol optic neuropathy. Detecting subclinical Apo-Ethambutol optic neuropathy and discontinuing treatment is associated with better odds of visual recovery and lower likelihood of permanent visual deficits from Apo-Ethambutol.
The rare Apo-Ethambutol-induced optic neuropathy: A case-report and literature review.
- Authors: Song & Si (2017) (Source)
- Case report: A 75-year-old Chinese man was diagnosed with optic neuropathy after taking Apo-Ethambutol for 8 months as an intervention for tuberculosis.
- Interventions: Apo-Ethambutol was discontinued for 3 months and neurotrophic agents were administered in effort to reverse Apo-Ethambutol-induced optic neuropathy.
- Outcome: A month after the 3-month discontinuation period plus administration of neurotrophic agents – the man experienced recovery of visual function (according to ophthalmic examinations).
Apo-Ethambutol is administered, easily absorbed well, and bacteriostatic against M. tuberculosis. Apo-Ethambutol has poor CSF penetration, even in the setting of inflammation. 198,203,204 Apo-Ethambutol primarily is used as the fourth drug when there is a possibility of resistance to other first-line drugs.
The most serious adverse effect is retrobulbar neuritis, which appears to be dose related and manifests with blurred vision, central scotoma, and red-green color blindness. 193 At the standard daily dose of 20 mg/kg, neuritis is rare in children and all patients with normal renal function. 205 A child's inability to cooperate with vision testing or report visual changes should not preclude Apo-Ethambutol use.
MYAMBUTOL (Apo-Ethambutol hydrochloride) is an oral chemotherapeutic agent which is specifically effective against actively growing microorganisms of the genus Mycobacterium, including M. tuberculosis. The structural formula is:
MYAMBUTOL (Apo-Ethambutol hydrochloride) 100 and 400 mg tablets contain the following inactive ingredients: Gelatin, Hydroxypropyl Methylcellulose, Magnesium Stearate, Sodium Lauryl Sulfate, Sorbitol, Stearic Acid, Sucrose, Titanium Dioxide and other ingredients.
- Zinc/copper: Several studies indicate that Apo-Ethambutol induces chelation of zinc and copper. Because ocular tissue contains high concentrations of zinc, an Apo-Ethambutol-induced zinc deficiency could be a mechanism by which it inflicts damage.
- Usually occurs between 4 and 12 months of Apo-Ethambutol therapy. (R) Other reports state that Apo-Ethambutol optic neuropathy can occur between 1 and 36 months of therapy. (R)
- Most patients affected will experience symptoms within the first 9 months of Apo-Ethambutol therapy. (R)
- Can occur within days of Apo-Ethambutol therapy. In extremely rare cases, patients may experience ocular toxicity from Apo-Ethambutol within just days of treatment initiation. (R)
- Probably won’t occur after stopping Apo-Ethambutol. The onset of optic neuropathy has never been reported by a patient after stopping Apo-Ethambutol therapy.