Antibiotics themselves do not typically cause tiredness or fatigue. Most of the tiredness experienced while taking antibiotics is usually due to the body fighting the infection rather than the medication directly causing fatigue. However, some specific antibiotics like vancomycin and, rarely, amoxicillin, azithromycin, and ciprofloxacin can cause fatigue in some people. Additionally, the disruption of good gut bacteria and side effects like nausea or dehydration from antibiotics may contribute to feelings of tiredness. If fatigue is severe or persistent, consulting a healthcare provider is recommended to determine the cause and adjust treatment if needed.