As with any medication, there are potential drug interactions with fosinopril. Taking fosinopril along with other medications, such as diuretics, lithium, or antacids, can change the way your body metabolizes these drugs. As a result, these drug interactions can cause your blood pressure to decrease too much, damage your kidneys, or decrease the absorption of fosinopril in your body. Therefore, it is important to discuss any potential drug interactions with your pharmacist or healthcare provider prior to taking fosinopril.