Blood Medication

OTC: Miconazole
Interaction: Warfarin

OTC: St Johns Wart
Interaction: Aspirin

OTC: Omeprazole and Esomeprazole
Interactions: Clopidogrel 


Psychiatric medication

OTC: St Johns Wart
Interaction: Sertraline 

Heart Medication

OTC: Antacid containing aluminium or magnesium
Interaction: Digoxin 

Antibiotics

OTC: Calcium, Magnesium or Iron
Interactions: Tetracyclines