Hello,
Thank you for the question and welcome to Healthcaremagic!
Cumbutol-800 is drug
Ethambutol which is primary drug in TB treatment. The usual side effects by this drug is eye problem like difficulty seeing, eye pain, unable to see and others like rash,
body pain, high uric acid, joint pain,
vomiting etc.
Its unlikely your
fainting episode to be caused by this drug in particular. If you have no yet checked your BP,ECG, Liver function,
Hemoglobin,uric acid lab tests it is good idea to get these done as these can be cause of your episode. Fainting can also be a one time episode due to stress,fatigue, vagal tone increase.
Get the above tests done and get your self examined by a local physician to make the decision. Do not avoid taking the drug or take it intermittently as this can lead to bacterial resistance and the infection will not be cured. Speak with your treating physician about your concerns.
Hope this cleared your query, Takecare!