Olmesartan ester tablets are utilized to treat high blood pressure; side effects include dizziness, diarrhea, and headache. Olmesartan ester tablets can antagonize the binding of angiotensin II to vascular smooth muscle AT1 receptors, thus inhibiting the vasoconstrictor effect of angiotensin II and lowering blood pressure. The drug may have side effects such as dizziness, diarrhea, headache, hematuria, pharyngitis, malaise, edema, abdominal pain, dyspepsia, tachycardia, arthritis, rash, hyperuricemia, hyperkalemia, and other side effects. Blood potassium levels should be tested during administration of the drug because it may cause hyperkalemia. The drug interacts with drugs such as aliskiren, colesevelam hydrochloride and lithium, so you should consult a healthcare professional before use. It is contraindicated in the following cases: children under 1 year of age; pregnant women and women who may become pregnant; hypersensitivity to the drug; diabetics taking Aliskiren. The drug can be secreted through breast milk and should be used by breastfeeding women after careful consideration. If you need to use the drug, please make sure to take the drug under the guidance of a doctor and strictly follow the doctor’s instructions, do not use the drug at will.