Other antihypertensives (additive BP lowering), verapamil/diltiazem (risk of severe bradycardia/heart block), digoxin (bradycardia), antiarrhythmics like amiodarone (conduction issues), NSAIDs (may reduce antihypertensive effect), clonidine (rebound hypertension if stopped improperly), insulin/oral antidiabetics (masked hypoglycemia), alcohol (increased dizziness)