What happens if you stop taking antihypertensive (blood pressure) medication?

Consequences of Stopping Antihypertensive Medications

Abruptly stopping antihypertensive medications can lead to rebound hypertension, increased risk of cardiovascular events, and potential life-threatening complications, especially with certain drug classes like beta-blockers and clonidine. 1, 2

Immediate Consequences of Discontinuation

• Rebound hypertension can occur within hours to days after stopping medications, particularly with centrally acting antiadrenergic drugs and beta-blockers 1
• Abrupt cessation may lead to sympathetic hyperactivity, causing tachycardia, sweating, anxiety, and tremors 2
• Patients may experience a rapid rise in blood pressure that can exceed pre-treatment levels, especially with short-acting medications 2
• Withdrawal syndromes are more common with high doses of multiple antihypertensive drugs 1

Drug-Specific Withdrawal Effects

• Beta-blockers: Abrupt discontinuation can cause rebound tachycardia, increased blood pressure, and potentially precipitate angina or myocardial infarction in patients with underlying coronary artery disease 3
• Clonidine and central alpha-agonists: May cause dangerous rebound hypertension with headache, agitation, and tremor within 24-72 hours 3, 1
• ACE inhibitors/ARBs: Generally have fewer acute withdrawal symptoms but can lead to gradual blood pressure elevation 3
• Calcium channel blockers: Rapid discontinuation of short-acting formulations may cause reflex tachycardia and blood pressure elevation 3

Long-Term Consequences

• Loss of cardiovascular protection, increasing risk of myocardial infarction, stroke, and heart failure 3
• Increased risk of cardiovascular events, especially in patients with pre-existing cardiovascular disease 3
• Potential for accelerated target organ damage, including cardiac, renal, and cerebrovascular complications 3
• Patients with uncontrolled hypertension have higher perioperative risk of cardiovascular disease, cerebrovascular events, and bleeding 3

Risk Factors for Severe Withdrawal Reactions

• Pre-existing coronary artery disease or heart failure 1
• Severe baseline hypertension (SBP ≥180 mm Hg or DBP ≥110 mm Hg) 3
• Renovascular or high-renin hypertension 1
• Use of multiple antihypertensive medications at high doses 1
• Older age and longer duration of hypertension 3

Safer Approach to Medication Discontinuation

• If discontinuation is necessary, medications should be tapered gradually over 7-10 days rather than stopped abruptly 1
• Close monitoring of blood pressure is essential during and after discontinuation 4
• Patients should be educated about potential withdrawal symptoms and when to seek medical attention 3
• For patients requiring temporary discontinuation for diagnostic testing, this should be done in a controlled setting with appropriate monitoring 4

Special Populations

• Perioperative patients: Continuing antihypertensive therapy throughout the perioperative period is reasonable for most patients 3
• Pregnant women: Careful management of antihypertensive discontinuation is critical, as severe hypertension increases risks to both mother and fetus 3
• Elderly patients: May be more sensitive to abrupt blood pressure changes and at higher risk for falls and orthostatic hypotension during medication adjustments 3

When Discontinuation Might Be Considered

• Mild hypertension patients with normal body weight, low salt intake, no alcohol consumption, and minimal target organ damage may successfully discontinue therapy under close supervision 5
• Young patients with well-controlled blood pressure on a single agent may be candidates for supervised step-down therapy 5
• Discontinuation should always be done with frequent blood pressure monitoring and physician supervision 5, 4

Remember that the safest approach is to continue antihypertensive medications as prescribed and to consult with a healthcare provider before making any changes to your treatment regimen 3.