Rifampicin (or rifampin) is an antibiotic used primarily for treating tuberculosis and certain bacterial infections, and is characterized by specific dosing guidelines depending on age and weight. The medication can lead to serious side effects, such as liver dysfunction and hypersensitivity reactions, and is contraindicated in certain patients, including those with liver impairment. Caution is advised with its use during pregnancy and in lactating women, and it is crucial to ensure proper medical supervision to mitigate risks of resistance and adverse effects.