SIDE EFFECTS: Dizziness, lightheadedness, or tiredness may occur as your body adjusts to the medication. Dry cough, nausea, or vomiting may also occur. If any of these effects last or get worse, tell your doctor or pharmacist promptly. Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects. Tell your doctor right away if you have any serious side effects, including: symptoms of a high potassium blood level (such as muscle weakness, slow/irregular heartbeat), fainting. Although quinapril may be used to prevent kidney problems or treat people who have kidney problems, it may also rarely cause serious kidney problems or make them worse. Your doctor will check your kidney function while you are taking quinapril. Tell your doctor right away if you have any signs of kidney problems such as a change in the amount of urine. This drug may rarely cause serious (possibly fatal) liver disease. Get medical help right away if you have any symptoms of liver damage, such as: nausea/vomiting that doesn't stop, loss of appetite, stomach/abdominal pain, yellowing eyes/skin, dark urine. A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing. This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist. In the US - Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch. In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

PRECAUTIONS: Before taking quinapril, tell your doctor or pharmacist if you are allergic to it; or to other ACE inhibitors (such as benazepril); or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details. Before using this medication, tell your doctor or pharmacist your medical history, especially of: history of an allergic reaction which included swelling of the face/lips/tongue/throat (angioedema), blood filtering procedures (such as LDL apheresis, dialysis), high level of potassium in the blood, liver disease. This drug may make you dizzy. Alcohol or marijuana can make you more dizzy. Do not drive, use machinery, or do anything that needs alertness until you can do it safely. Limit alcoholic beverages. Talk to your doctor if you are using marijuana. Too much sweating, diarrhea, or vomiting may cause loss of too much body water (dehydration) and increase your risk of lightheadedness. Report prolonged diarrhea or vomiting to your doctor. Be sure to drink enough fluids to prevent dehydration unless your doctor directs you otherwise. Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products). This product may increase your potassium levels. Before using potassium supplements or salt substitutes that contain potassium, consult your doctor or pharmacist. Older adults may be more sensitive to the side effects of this drug, including dizziness and increases in potassium level. This medication is not recommended for use during pregnancy. It may harm an unborn baby. Consult your doctor for more details. See also Warning section. This medication passes into breast milk. Consult your doctor before breast-feeding.

DRUG INTERACTIONS: See also Precautions section. Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval. Some products that may interact with this drug include: aliskiren, gold injections, lithium, sacubitril, certain drugs that weaken the immune system/increase the risk of infection (such as everolimus, sirolimus), drugs that may increase the level of potassium in the blood (such as ARBs including losartan/valsartan, birth control pills containing drospirenone). This product contains magnesium which can interfere with your body's ability to absorb certain drugs, especially if you take them around the same time. These drugs include quinolone antibiotics (such as ciprofloxacin, levofloxacin), tetracycline antibiotics (such as doxycycline, minocycline), thyroid medications (such as levothyroxine), and drugs for osteoporosis (bisphosphonates such as alendronate). This is not a complete list. Ask your doctor or pharmacist how long to wait between doses and when you should take your medications. Some products have ingredients that could raise your blood pressure or worsen your heart failure. Tell your pharmacist what products you are using, and ask how to use them safely (especially cough-and-cold products, diet aids, or NSAIDs such as ibuprofen/naproxen). A very serious reaction may occur if you are getting injections for bee/wasp sting allergy (desensitization) and are also taking quinapril. Make sure all your doctors know which medicines you are using.

OVERDOSE: If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center. Symptoms of overdose may include: severe dizziness, fainting.