Enalapril

How it works

     * Enalapril may be used in the treatment of high blood pressure or
       heart failure and works by inhibiting an enzyme called
       angiotensin-converting enzyme (ACE). This enzyme is involved in the
       production of angiotensin II, a powerful vasoconstrictor (narrows
       arteries), which also stimulates the release of the hormone
       aldosterone from the adrenal glands (aldosterone can increase blood
       pressure). By inhibiting this enzyme, enalapril opens up the
       arteries (vasodilates) and lowers blood pressure. This also reduces
       how hard the heart has to work to pump blood around the body,
       helping relieve symptoms of heart failure.
     * Enalapril belongs to a group of medicines known as
       angiotensin-converting enzyme (ACE) inhibitors.

Upsides

     * May be used for the treatment of high blood pressure or heart
       failure.
     * Enalapril may also be given to people with evidence of dysfunction
       of the left ventricle of their heart, but currently without
       symptoms of heart failure (a condition called left ventricular
       dysfunction). Trials have shown enalapril reduces the development
       of heart failure in people with this condition and reduces the
       incidence of hospitalization.
     * In high blood pressure, enalapril reduces both lying down and
       standing blood pressure without a significant orthostatic effect
       (this is the drop sometimes seen when going from sitting to
       standing). However, dehydrated patients may be at higher risk of an
       orthostatic effect.
     * In people with heart failure, enalapril decreases heart size and
       increases how much blood the heart can pump out. It also increases
       exercise tolerance, without having much of an effect on heart rate.
       Enalapril use can decrease the severity of heart failure, rates of
       hospitalization and symptoms such as shortness of breath and
       tiredness. Beneficial effects remain apparent with continued
       dosing.
     * Effective alone or in combination with other treatments for high
       blood pressure.
     * Available as oral tablets, a suspension, and in an injectable form.
     * Generic enalapril is available.

Downsides

   If you are between the ages of 18 and 60, take no other medication or
   have no other medical conditions, side effects you are more likely to
   experience include:
     * A headache, dizziness, and fatigue are the most common side
       effects.
     * A dry cough which usually resolves on discontinuation of therapy.
       This side effect is common to all ACE inhibitors.
     * Occasionally may cause excessive lowering of blood pressure but the
       risk is higher in those on diuretic therapy or who are sodium
       depleted or dehydrated.
     * Rarely may cause angioedema of the face, lips, tongue, throat, and
       extremities. May occur at any time during treatment. Immediate
       discontinuation is warranted if angioedema is affecting breathing.
     * Also rare is the development of blood disorders and liver failure.
     * May increase blood potassium levels, the risk is higher in people
       with diabetes, poor kidney function, and using potassium-sparing
       diuretics or taking potassium supplements.
     * May have less of a blood pressure-lowering effect in patients of
       African-American descent compared to those without this ethnicity.
       Also, the incidence of angioedema (skin reaction associated with
       head and neck swelling) is higher in African-American patients.
     * May not be suitable for some people including those with kidney
       disease, liver disease, a history of blood clots, or electrolyte
       imbalances.
     * Can interact with a number of other medications (including NSAIDs
       and lithium) - consult your prescribing doctor before taking any
       other medications including those brought over the counter. People
       who have diabetes should not take enalapril and aliskiren together.

   Notes: In general, seniors or children, people with certain medical
   conditions (such as liver or kidney problems, heart disease, diabetes,
   seizures) or people who take other medications are more at risk of
   developing a wider range of side effects. For a complete list of all
   side effects, [84]click here.

Bottom Line

   Enalapril may be used for the treatment of heart failure or high blood
   pressure. Enalapril, as with other ACE inhibitors, may not be as
   effective in people of African-American descent.

Tips

     * May be taken with or without food.
     * Treatments that lower blood pressure, such as enalapril, should
       always be part of a comprehensive cardiovascular risk reduction
       plan that also targets, if appropriate, cholesterol lowering,
       diabetes risk reduction, exercise, weight loss, and smoking
       cessation.
     * Ensure adequate hydration before starting enalapril.
     * If you are prescribed enalapril suspension, shake it well before
       measuring the dose with the dosing syringe provided or a properly
       calibrated measuring cup. Do not use a kitchen teaspoon. Store the
       suspension in the refrigerator, do not freeze. Throw away any
       unused suspension after 60 days.
     * Enalapril may make you feel dizzy, especially in the first few
       weeks of therapy and when going from a sitting or lying down
       position to standing. Always take your time when standing up. Talk
       with your doctor if this feeling persists.
     * Call emergency services if your throat, face or lips show signs of
       swelling.
     * Report any signs of fever or a sore throat to your doctor who may
       carry out further tests to ensure it is not neutropenia (a decrease
       in white blood cells).
     * Also call your doctor if you develop chest pain, a change in your
       heartbeat or muscle contraction or weakness.
     * Your doctor should monitor your blood pressure, kidney function and
       potassium levels regularly.
     * For high blood pressure, continue this medication even if you feel
       well. High blood pressure does not usually have symptoms.
     * Do not use salt substitutes or potassium supplements while taking
       enalapril, unless recommended by your doctor.
     * If you also have diabetes, you may need to monitor your blood sugar
       levels more closely during the first few weeks of enalapril
       therapy.
     * Do not use enalapril if you are pregnant or trying to become
       pregnant or if you are breastfeeding.
     * Limit your alcohol intake while taking enalapril because enalapril
       can further lower your blood pressure and increase the risk of side
       effects.

Response and Effectiveness

     * Peak concentrations of enalapril occur within an hour of oral
       administration, 15 minutes after IV administration. Enalapril is
       hydrolyzed to enalaprilat once inside the body; enalaprilat is a
       more potent inhibitor of angiotensin converting enzyme than
       enalapril. Peak concentrations of enalaprilat occur within three to
       four hours after administration of enalapril.
     * Blood pressure lowering effects are seen within an hour of oral
       administration with peak effects achieved by four to six hours.
       Blood pressure lowering effects are maintained for at least 24
       hours, although in some patients these effects may diminish towards
       the end of the 24 hour period. It may take several weeks before
       optimal blood pressure lowering effects are achieved. Abrupt
       withdrawal of enalapril has not resulted in an abrupt increase in
       blood pressure; however, as with most antihypertensive drugs, it is
       best to discontinue enalapril slowly.

References