Quinapril Hydrochloride (Accupril)

Brand Name - Accupril

  • Type of Drug: Angiotensin-converting-enzyme (AGE) inhibitor.
  • Prescribed for: High blood pressure and congestive heart failure.

Quinapril Hydrochloride (Accupril) General Information

ACE inhibitors work by preventing the conversion of a hormone called angiotensin I to another hormone called angiotensin II, a potent blood vessel constrictor. Preventing this conversion relaxes blood vessels and helps to reduce blood pressure and relieve the symptoms of heart failure by making it easier for a failing heart to pump blood around your body. The production of other hormones and enzymes that participate in the regulation of blood vessel dilation is also affected by the ACE inhibitors and probably plays a role in the effectiveness of these medicines. Quinapril begins working about an hour after you take it and lasts for a full 24 hours.

Some people who start taking an ACE inhibitor after they are already on a diuretic experience a rapid blood-pressure drop after their first dose or when the dose is increased. To prevent this from happening, you may be told to stop taking the diuretic 2 or 3 days before starting the ACE inhibitor or increase your salt intake during that time. The diuretic may then be restarted gradually. Heart failure patients generally have been on Digoxin and a diuretic before beginning treatment with an ACE inhibitor.

Quinapril Hydrochloride (Accupril) Cautions and Warnings

Do not take Quinapril if you have had an allergic reaction to it in the past. It can, rarely, cause very low blood pressure, and it can affect your kidneys, especially if you have congestive heart failure. It is advisable for your doctor to check your urine for changes during the first few months of treatment.

Dosage adjustment of Quinapril is necessary if you have reduced kidney function, since it is eliminated from the body mainly by your kidneys. Ironically, ACE inhibitors may cause a decline in kidney function on their own.

Rarely, Quinapril affects white-blood-cell count, possibly increasing your susceptibility to infection. Blood counts should be monitored periodically.

Quinapril Hydrochloride (Accupril) Possible Side Effects

  • Most common: dizziness, tiredness, headache, and chronic cough. The cough usually goes away a few days after you stop taking the medicine.
  • Less common: nausea, vomiting, and abdominal pains.
  • Rare: heart palpitations, rapid heartbeat, chest pain, angina, heart attack, stroke, abdominal pain, fainting, dizziness when rising from a sitting or lying position, sleepiness, feelings of ill health, depression, nervousness, constipation, dry mouth, inflammation of the pancreas, sweating, skin rash or peeling, itching, sun sensitivity, kidney failure, reduced white-blood-cell or blood-platelet counts, stomach or intestinal bleeding, high blood pressure, shock, flushing or redness, back pain, visual disturbances, sore throat, and viral infections.

Drug Interactions

  • The blood-pressure-lowering effect of Quinapril is additive with diuretic drugs and beta blockers. Any other drug that causes a rapid blood-pressure drop should be used with caution if you are, taking ACE Inhibitors.
  • Quinapril may increase potassium levels in your blood, especially when taken with Dyazide or other potassium-sparing diuretics.
  • Quinapril may increase the effects of Lithium; this combination should be used with caution.
  • Antacids may reduce the amount of Quinapril absorbed into the blood. Separate doses of these two medicines by at least 2 hours.
  • Quinapril decreases the absorption of Tetracycline by about 1/3, possibly because of the high Magnesium content of Quinapril tablets.
  • Quinapril may increase blood levels of Digoxin, possibly increasing the chance of Digoxin-related side effects.
  • Capsaicin may cause or aggravate the cough associated with Quinapril therapy.
  • Indomethacin may reduce the blood-pressure-lowering effects of Quinapril.
  • Phenothiazine tranquilizers and antiemetics may increase the effects of Quinapril.
  • The combination of Allopurinol and Quinapril increases the chance of a drug reaction.

Quinapril Hydrochloride (Accupril) Food Interactions

Quinapril is affected by high-fat food in the stomach and should be taken on an empty stomach or at least 1 hour before or 2 hours after a meal.

Usual Dose

Adult: 10 to 80 mg, once a day. People with kidney disease may require less medicine.


The principal effect of Quinapril overdose is a rapid drop in blood pressure, as evidenced by dizziness or fainting. Take the overdose victim to a hospital emergency room at once. ALWAYS bring the medicine bottle.

Quinapril Hydrochloride (Accupril) Special Information

Call your doctor at once if you develop swelling of the face or throat, if you have sudden difficulty breathing, or if you develop a sore throat, mouth sores, abnormal heartbeat, chest pain, a persistent rash, or loss of taste perception.

AGE inhibitors can cause unexplained swelling of the face, lips, hands and feet. This swelling can also affect the larynx (throat) and tongue and interfere with breathing. If this happens, the victim should be taken to a hospital emergency room at once for treatment.

You may get dizzy if you rise to your feet too quickly from a sitting or lying position.

Avoid strenuous exercise and/or very hot weather because heavy sweating or dehydration can cause a rapid blood-pressure drop.

Avoid nonprescription diet pills, decongestants, and stimulants that can raise blood pressure.

If you forget to take a dose of Quinapril, take it as soon as you remember. If it is within 8 hours of your next dose, skip the one you forgot and continue with your regular schedule. Do not take a double dose.

Quinapril Hydrochloride (Accupril) Special Populations

ACE inhibitors have caused low blood pressure, kidney failure, slow formation of the skull, and death in developing fetuses when taken during the last 6 months of pregnancy. Women who are pregnant should not take Quinapril. Women who may become pregnant while taking Quinapril should use an effective contraceptive method and stop taking the medicine if they do become pregnant.

Relatively small amounts of Quinapril pass into breast milk, and the effect on a nursing infant is likely to be minimal. However, nursing mothers who must take this drug should consider an alternative feeding method since infants, especially newborns, are more susceptible to the effects of these medicines than adults.

Older adults may be more sensitive to the effects of Quinapril than younger adults because of the possibility of kidney impairment and should begin at 10 mg daily. Your Quinapril dosage must be individualized to your needs.