Use caution when driving, operating machinery, or performing other hazardous activities. Lisinopril may cause dizziness or drowsiness. If you experience dizziness or drowsiness, avoid these activities and notify your doctor. Also use caution when rising from a sitting or lying position. Use alcohol cautiously. Alcohol may increase drowsiness and dizziness while you are taking lisinopril. Alcohol may further lower blood pressure and increase drowsiness and dizziness when you are taking lisinopril. Do not use salt substitutes or potassium supplements while taking lisinopril except under the supervision of your doctor. Heavy sweating, vomiting, diarrhea, or other causes of fluid loss may lead to very low blood pressure, dizziness, and fainting during therapy with lisinopril. Maintain proper fluid intake to prevent dehydration and related side effects. First doses of lisinopril or any ACE inhibitor should be taken under observation if the patient also is taking diuretics (water pills). In such patients, blood pressure can drop quickly (though this is unusual). In general, lisinopril should not be taken with potassium supplements or diuretics that conserve potassium, e.g., Dyazide, since blood potassium levels may rise to dangerous levels. Lisinopril should not be taken during pregnancy.

First doses of lisinopril can cause dizziness due to a drop in blood pressure. Lisinopril should be stopped if there are symptoms or signs of an allergic reaction including feelings of swelling of the face, lips, tongue or throat. Severe allergic reactions (anaphylaxis) and hives occasionally occur.

An uncommon but dangerous side effect is a drop in the white blood cells which fight infection. Cough is a known side effect of this drug.

Lisinopril can impair the function of the kidneys, and every person taking this medication should have their kidney function checked. Lisinopril rarely can cause nausea, headaches, anxiety, insomnia, drowsiness, nasal congestion and sexual dysfunction.

• If you experience any of the following serious side effects, stop taking lisinopril and call your doctor immediately or seek emergency medical treatment:
  • an allergic reaction (difficulty breathing; closing of your throat; swelling of your lips, tongue, or face; or hives);
  • difficulty breathing;
  • little or no urine;
  • an irregular heartbeat or changes in your heartbeat;
  • chest pain;
  • severe dizziness or fainting; or
  • signs of an infection including a sore throat or a fever.
• Other, less serious side effects may be more likely to occur. Continue to take lisinopril and talk to your doctor if you experience
  • mild dizziness or lightheadedness;
  • headache;
  • unusual fatigue or weakness;
  • dry, tickling cough;
  • muscle cramps;
  • numbness or tingling in the hands, feet, arms, or legs;
  • nausea, vomiting, or diarrhea;
  • a rash; or
  • impotence.
• Side effects other than those listed here may also occur. Talk to your doctor about any side effect that seems unusual or that is especially bothersome.