When is ethambutol contraindicated?
Ethambutol is contraindicated in patients who are known to be hypersensitive to this drug, in patients with known optic neuritis, in patients who are unable to appreciate and report visual side effects or changes in vision (e.g., young children, unconscious patients.
How is ethambutol metabolized?
Ethambutol is mainly oxidized by an aldehyde dehydrogenase to an aldehyde metabolite, followed by conversion to the dicarboxylic acid 2,2′-(ethylinediimino)di-butyric acid. Ethambutol is 50% eliminated in the urine as the unmetabolized parent compound and 8-15% as inactive metabolites.
Which anti TB drug is safe in renal failure?
Rifampicin 10mg/kg/day up to 600mg No dose adjustment required No dose adjustment required No dose adjustment required No dose adjustment required No dose adjustment required • Can be used safely in renal disease.
Which anti TB drug causes nephrotoxicity?
Rifampicin is a widely used anti-tuberculosis agent. On rare occasions, the drug can cause adverse effects such as acute renal failure, though most regain complete renal function upon discontinuation of therapy.
What is ethambutol toxicity?
Ethambutol is an antimicrobial agent used frequently to treat tuberculosis. The most commonly recognized toxic effect of ethambutol is optic neuropathy, which generally is considered uncommon and reversible in medical literature.
What do I monitor for ethambutol?
The patient’s awareness of potential ethambutol toxicity should be reinforced, and the patient may be taught to check visual acuity, color vision, and central field at home with a smartphone-based app or given a visual acuity chart printout and an Amsler’s grid chart.
Why would you discontinue ethambutol?
Ethambutol can cause vision problems that may be a sign that you should stop taking the medicine. You may not be able to take 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.
Is ethambutol toxicity reversible?
Delayed onset ocular ethambutol toxicity is usually considered to be reversible following prompt withdrawal of the drug.
How is ethambutol toxicity diagnosed?
The optical coherence tomography (OCT) has proven to be a useful tool for the detection of toxic optic neuropathy and changes may be seen in the retinal nerve fiber and ganglion cell layers. While changes on the OCT are not specific to toxic optic neuropathy, they may help in the prognosis and follow-up.
What do I monitor for Ethambutol?
Why is Ethambutol given isoniazid?
Combination therapy reduces the development of drug resistance (reduction in the effectiveness of medication) as the bacteria causing TB develops drug resistance easily when monotherapy is given even for shorter periods. ETHAMBUTOL+ISONIAZID helps to reduce the symptoms and control the disease effectively.
Can you stop ethambutol?
Continue to take the tablets regularly – do not stop taking ethambutol unless your doctor tells you to stop. This is because it is important for you to complete the course of medicine so that the infection does not come back.
How is ethambutol toxicity treated?
Currently, there is no effective treatment for EON. However, if the condition is detected early and the drug is discontinued promptly (before the development of irreversible optic atrophy), between 30-64% of patients have been reported to show visual improvements over a course of several months.
How do you manage ethambutol toxicity?
Once ethambutol-induced ocular toxicity is recognised, the drug should be immediately stopped and the patient referred to an ophthalmologist for further evaluation. Presently, therapy discontinuation is the only effective management strategy that can stop the progression of vision loss and allow recovery of vision.
What are the renal side effects of lithium?
The most common renal side effect of lithium is of concentrating urine despite normal or elevated concentrations of the antidiuretic hormone vasopressin (Table 1). The concentrating defect leads to decreased urine osmolality and increased urine volume (polyuria).
Can lithium cause chronic tubulointerstitial nephritis?
Despite these variable findings within the literature, the predominant view is one of lithium having the ability to cause a chronic tubulointerstitial nephritis which leads to progressive CKD over a period of many years and ESKD in about 1.5% of long term lithium users [ 9 ].
Can modern treatment principles eliminate lithium-induced renal failure?
The impact of modern treatment principles may have eliminated lithium-induced renal failure. J Psychopharmacol. 2014;28 (2):151–4. 26. Kessing LV, Gerds TA, Feldt-Rasmussen B, Andersen PK, Licht RW.
What increases the risk of lithium toxicity in patients with polyuria?
Importantly, patients with polyuria that do not consume sufficient amounts of fluids are at a high risk of becoming volume-depleted, further increasing the risk of lithium toxicity (Vestergaard et al. 1979; Vestergaard and Amdisen 1981; Smigan et al. 1984).