People who are allergic to ingredients found in anti-diarrhea medicine should not take it, states WebMD. Also, people with certain medical conditions such as a history of AIDS, high fever, liver problems and black, tarry stools should not take the medicine without first speaking to a doctor.
Individuals who are currently taking or have recently taken antibiotics should not take anti-diarrhoeal medicines without first speaking to a doctor, states WebMD. This is especially true if an individual is experiencing symptoms such as bloody stools, persistent diarrhea or stomach pain. Individuals who must control the amount of aspartame or phenylalanine are advised to first contact a doctor, as some anti-diarrheal medicines contain those ingredients. Women who are pregnant or nursing should likewise contact a doctor before using the medicine.