If an overdose of antihypertensive drugs is taken, blood pressure will drop, and an overdose of different antihypertensive drugs will also cause corresponding toxic side effects. Once an overdose of antihypertensive medication is taken, patients are most likely to experience hypotensive reactions, such as dizziness, weakness, or even symptoms of brain ischemia such as black clouding, and in severe cases, shock may occur and can be life-threatening. Different antihypertensive drug overdoses cause different toxic side effects. For example, antihypertensive drugs containing diuretics can cause polyuria, electrolyte disorders, and even life-threatening effects due to severe low potassium and sodium; in the case of beta-blockers, severe bradycardia and even sinus arrest can occur; in the case of calcium antagonist overdose, adverse reactions such as increased heart rate, flushing, panic and headache can occur. If it is a compound preparation or multiple antihypertensive drug overdose, it can cause more serious toxic side effects. If you take an overdose of antihypertensive drugs, you should immediately go to the hospital for active treatment, which can be done by gastric lavage and diarrhea to promote the excretion of drugs from the body. If an overdose of antihypertensive medication is prolonged, gastric lavage and diarrhea will not promote the elimination of the medication from the body, and dialysis can be used to remove the medication that has been absorbed into the blood. Therefore, it is important to take antihypertensive drugs regularly and not to overdose on antihypertensive drugs, and if you miss a dose, you should not make up for the previous missed dose in the next dose. Moreover, antihypertensive drugs should be kept in a safe place to prevent children from taking them by mistake.