1 What is Quinapril?

Brand: Quinapril

Generic: Quinapril and Hydrochlorothiazide

Quinapril and hydrochlorothiazide combination is a prescription-only product which consists of two antihypertensive agents used in patients with high blood pressure (hypertension).

Unchecked hypertension for a prolonged time causes “extra” workload on the heart and blood vessels, resulting in damages to the blood vessels of the brain, heart, and kidneys. Over time, hypertension can lead to a stroke, heart failure, or kidney failure.

Quinapril is an angiotensin-converting enzyme (ACE) inhibitor that works by inhibiting the formation of blood vessel constricting chemicals in the body whereas hydrochlorothiazide is a diuretic (water pill) that works by increasing the rate of urine formation.

Both these actions have combined effect in reducing the blood pressure. It is available in tablet form.

2 What to Know Before Using

Before using Quinapril, you must know all about the risks and complications associated with it.

Keep the following factors in mind before using these medicines:

Allergies: Inform your doctor about the allergies you have, such as to this medication, other medications, or to foods, dyes, or preservatives.

Pediatric: Safety and efficacy of this product in kids have not been well documented. Therefore, consult your doctor before using this product in your children.

Geriatric: This product may be used in elderly after adjusting the doses. Exercise recommended precautions during the use.

Pregnancy: It falls under category D for all trimesters meaning that its use during pregnancy is risky, but may be recommended in a serious situation after assessing the risk to benefit ratio.

Breastfeeding: It may be used in a nursing mother after assessing risks and benefits of the use.

Drug Interactions: Taking two medicines together can be harmful due to possible interactions. In other cases, even if there is a possible interaction between two medicines your doctor may advise you to take them together after adjusting the dose or issuing precautions.

Here is a list of the medicines which in general are not recommended to be used with this medicine.

Inform your doctor if you are using any of these medicines:

  • Aliskiren
  • Dofetilide
  • Sacubitril

Though usually not recommended, your doctor may decide, after adjusting dose or frequency of one or both medicines, to use this medicine with any of the following medicines:

  • Acetyldigoxin
  • Recombinant alteplase
  • Amiloride
  • Amphetamine
  • Azathioprine
  • Azilsartan
  • Cilexetil
  • Canrenoate
  • Cyclophosphamide
  • Deslanoside
  • Digitalis
  • Droperidol
  • Eplerenone
  • Everolimus
  • Flecainide
  • Ketanserin
  • Levomethadyl
  • Lithium
  • Losartan
  • Mercaptopurine
  • Methotrexate
  • Ouabain
  • Potassium
  • Proscillaridin
  • Sotalol
  • Spironolactone
  • Triamterene
  • Trimethoprim

Rarely and only when absolutely needed, this medicine may be used with the following medicines even if using them together may put you at risk of certain side effects.

In such cases, you may have to take the adjusted dose or change the frequency of intake.

  • Aceclofenac
  • Acemetacin
  • Amtolmetin Guacil
  • Aspirin
  • Azosemide
  • Bemetizide
  • Bendroflumethiazide
  • Benzthiazide
  • Bepridil
  • Bromfenac
  • Bufexamac
  • Bumetanide
  • Bupivacaine
  • Bupivacaine
  • Liposome
  • Buthiazide
  • Capsaicin
  • Carbamazepine
  • Celecoxib
  • Chlorothiazide
  • Chlorthalidone
  • Cholestyramine
  • Choline Salicylate
  • Clonixin
  • Clopamide
  • Cyclopenthiazide
  • Cyclothiazide
  • Delapril
  • Dexibuprofen
  • Dexketoprofen
  • Diclofenac
  • Diflunisal
  • Dipyrone
  • Droxicam
  • Enalapril
  • Ethacrynic Acid
  • Etodolac
  • Etofenamate
  • Etoricoxib
  • Felbinac
  • Fenoprofen
  • Fepradinol
  • Feprazone
  • Floctafenine
  • Flufenamic Acid
  • Flurbiprofen
  • Fosinopril
  • Furosemide
  • Ginkgo
  • Gold Sodium Thiomalate
  • Gossypol
  • Hydrochlorothiazide
  • Hydroflumethiazide
  • Ibuprofen
  • Imidapril
  • Indapamide
  • Indomethacin
  • Ketoprofen
  • Ketorolac
  • Lithium
  • Lornoxicam
  • Loxoprofen
  • Lumiracoxib
  • Meclofenamate
  • Mefenamic Acid
  • Meloxicam
  • Methyclothiazide
  • Metolazone
  • Moexipril
  • Morniflumate
  • Nabumetone
  • Naproxen
  • Nepafenac
  • Nesiritide
  • Niflumic Acid
  • Nimesulide
  • Oxaprozin
  • Oxyphenbutazone
  • Parecoxib
  • Pentopril
  • Perindopril
  • Phenylbutazone
  • Piketoprofen
  • Piretanide
  • Piroxicam
  • Polythiazide
  • Proglumetacin
  • Propionic Acid
  • Propyphenazone
  • Proquazone
  • Quinapril
  • Quinethazone
  • Salicylic Acid
  • Salsalate
  • Sodium Salicylate
  • Spirapril
  • Sulindac
  • Tiaprofenic Acid
  • Tolfenamic Acid
  • Tolmetin
  • Topiramate
  • Torsemide
  • Trandolapril
  • Trichlormethiazide
  • Valdecoxib
  • Xipamide
  • Zofenopril

Other Interactions: Taking your medicine together with certain foods or items such as alcohol or tobacco may cause undesirable interactions. Talk to your doctor to know if using this medicine with food, alcohol, or tobacco is safe.

Inform your doctor if you have any other medical conditions, including:

  • History of angioedema (swelling)
  • Anuria (suppressed urine formation)
  • Patients with diabetes or kidney conditions who are also taking aliskiren
  • Allergic to a sulfa drug such as sulfamethoxazole): Do not use this medicines.
  • Kidney impairment
  • Severe cases of congestive heart failure
  • Diabetes
  • Abnormal blood levels of electrolytes, such as high or low calcium, magnesium, potassium, or sodium
  • Dehydration
  • Certain types of glaucoma
  • Gout
  • Heart or blood vessel problems
  • Hypercholesterolemia (high blood cholesterol)
  • Hypertriglyceridemia (high blood fats)
  • Kidney or liver problems
  • Vision troubles such as acute myopia
  • Systemic lupus erythematosus (SLE): Use cautiously.

3 Proper Usage

To use Quinapril properly, you must follow all instructions given by your doctor.

Here are some points to consider:

  • The use of this medicine should be reserved for the conditions when other treatments have become ineffective or unbearable.
  • Remember that hypertension is a chronic disease. The key to controlling this often insidious condition is a combination of medicine, low-sodium diet, and weight management.
  • Follow your doctor’s instructions while taking any medicine including Rauwolfia alkaloids.
  • Do not get disheartened if your doctor prescribes you such medicines for a lifetime.
  • Serious health conditions that may arise from uncontrolled hypertension include heart failure, blood vessel disease, stroke, or kidney disease.

Dosing: For best results, follow your doctor to know what amount of medicine you should take in a single dose.

The doses of a medicine can differ according to the conditions for which it is being prescribed, your age and your overall health status. Remember your doses can differ.

Consult your doctor if you have anything to ask.

The doses of tablets for high blood pressure are:

  • Adults: One tablet a day with or without food. The dose may be increased as required.
  • Children: Your doctor will decide the use and dose.

Missed Dose: Take your missed dose once you remember but avoid it if it’s time to take your next dose, and follow your normal dosing schedule. Avoid taking double doses to make up for the missed dose.


  • Store in a closed container at room temperature.
  • Keep away from heat, moisture, and direct light.
  • Do not freeze.
  • Keep away from children.
  • Discard any unused or expired medicines.

4 Precautions to Take

Before using Quinapril, there are some precautions you must take. Your progress should be regularly monitored to determine if you are responding to the treatment. You may need to get your blood and urine tested to look for any undesirable effects.

If you are pregnant and using this medicine, the baby in your womb might be at risk. Avoid getting pregnant by using appropriate contraceptive measures. If you suspect of getting pregnant, inform your doctor immediately.

Seek immediate medical help if you have:

  • Symptoms of a life-threatening allergic condition, anaphylaxis, such as skin rashes, itching, hoarseness, breathing and swallowing difficulties, or swollen hands, face, or mouth.
  • Severe abdominal pain (nausea or vomiting may be present or absent), indicating intestinal angioedema.
  • Pain in the upper stomach, light colored stools, pale urine, decreased appetite, nausea, excessive tiredness, or yellowish eyes or skin, indicating a serious liver trouble.
  • Stomach pain, confusion, breathing difficulties, abnormal heartbeat, nausea or vomiting, nervousness, numbness or tingling sensations in the hands, feet, or lips, heavy legs, indicating dangerously high blood level of potassium (hyperkalemia). Do not use potassium-containing supplements without first consulting your doctor.
  • Vision problems such as blurry vision, reading problems, or eye pain, indicating a serious trouble with your eyes.
  • Severe nausea, vomiting, or diarrhea, which may lead to dehydration.
  • Fever, chills, or a sore throat, indicating an infection.

You may feel dizzy or lightheaded while taking this medicine. Therefore, exercise extra caution while driving, using machines or doing any activity that requires alertness.

Remember this medicine can interfere with blood or urine sugar tests. Talk to your doctor if you are concerned.

Make sure any other doctor or dentist you visit knows about your intake of this medicine.

Consult your doctor before using any nonprescription medicines for suppressing hunger, asthma, colds, cough, hay fever, or sinus problems, as this medicine may increase your blood pressure.

5 Potential Side Effects

Make sure you meet with your doctor in using Quinapril to avoid unwanted potential side effects.

Consult your doctor immediately if you have any of the following side effects:

Less common:

  • Breathing problems
  • Chest discomfort
  • A cough with sputum
  • Diarrhea


Mild and non-serious side effects usually go away on their own without requiring medical intervention. You may also ask your doctor to learn more about how you may prevent or reduce the side effects.

Talk to your doctor if the side effects persist or worry you, including:

Less common:

  • Cough
  • Excessive sleepiness or drowsiness
  • Weakness


  • Back pain
  • Concentration problems
  • Decreased appetite
  • Difficult bowel evacuation
  • Irritability
  • Mental depression
  • Sleep problems
  • Vision problems

The side effects of the medicine are not limited to the ones listed above. Call your doctor immediately if you experience any side effects that are uncommon or worry you. To report side effects to the FDA, contact at 1-800-FDA-1088.