BMA Concise Guide to Medicine & Drugs

Irbesartan

Brand name Aprovel

Used in the following combined preparation CoAprovel

QUICK REFERENCE

Drug group Vasodilator and antihypertensive drug

Overdose danger rating Medium

Dependence rating Low

Prescription needed Yes

Available as generic No

GENERAL INFORMATION

Irbesartan is a member of the group of vasodilator drugs (drugs that widen blood vessels) called angiotensin II blockers and is used to treat hypertension (high blood pressure). It is also used to protect the kidneys in people with Type 2 diabetes who have hypertension and impaired kidney function.

Unlike ACE inhibitors, irbesartan does not cause a persistent dry cough. Irbesartan is also available in combination with a diuretic (CoAprovel), which may increase its blood-pressure-lowering effect.

INFORMATION FOR USERS

Your drug prescription is tailored for you. Do not alter dosage without checking with your doctor.

How taken/used Tablets.

Frequency and timing of doses Once daily.

Adult dosage range 150mg (maintenance dose), increased to 300mg if needed; 75mg may be used in people over 75 years and those on haemodialysis.

Onset of effect Within 1 hour. Blood pressure is lowered within 1–2 weeks, and maximum beneficial effect occurs 4–6 weeks from start of treatment.

Duration of action 24 hours.

Diet advice None.

Storage Keep in original container at room temperature out of the reach of children.

Missed dose Take as soon as you remember. If your next dose is due within 8 hours, take a single dose now and skip the next.

Stopping the drug Do not stop the drug without consulting your doctor. Stopping the drug may lead to worsening of the underlying condition.

Exceeding the dose An occasional unintentional extra dose is unlikely to be a cause for concern. Large overdoses may cause dizziness, fainting, and a faint pulse or slow heart rate. Notify your doctor.

POSSIBLE ADVERSE EFFECTS

Adverse effects are usually mild and transient. Common ones include dizziness, fatigue, flushing, and nausea. Discuss with your doctor if these are severe. More rarely, there may be headache or muscle or joint pains; talk to your doctor if these are severe or if you develop a rash. If there is swelling of the lips or face, stop taking the drug and contact your doctor promptly. An exagggerated drop in blood pressure may occur if you take the drug when dehydrated.

INTERACTIONS

Diuretics There is a risk of a sudden fall in blood pressure if these drugs are being taken when irbesartan treatment is started. They may also affect sodium and potassium levels in the blood.

Potassium supplements, potassium-sparing diuretics, and ciclosporin Used with irbesartan, these drugs may raise levels of potassium in the blood.

Antihypertensives increase the effects of irbesartan.

Lithium Irbesartan increases the blood levels and toxicity of lithium.

NSAIDs Some of these drugs may reduce the blood-pressure-lowering effects of irbesartan, and there is a risk that they may worsen kidney function.

ACE inhibitors (e.g. enalapril, captopril, lisinopril, or ramipril) and potassium salts may increase potassium levels when taken with irbesartan.

SPECIAL PRECAUTIONS

Be sure to tell your doctor if:

· You have heart problems, including heart failure.

· You have kidney problems or stenosis of the kidney’s arteries.

· You have lactose/galactose intolerance or glucose/galactose malabsortion.

· You are taking other medicines.

Pregnancy Not prescribed. If you become pregnant during treatment, consult your doctor without delay.

Breast-feeding Safety not established. Discuss with your doctor.

Infants and children Not prescribed.

Over 60 Increased risk of adverse effects. Reduced dose may therefore be necessary.

Driving and hazardous work Avoid such activities until you have learned how irbesartan affects you because the drug can cause dizziness and fatigue.

Alcohol Regular intake of excessive alcohol may raise the blood pressure and reduce the effectiveness of irbesartan.

PROLONGED USE

No special problems.

Monitoring Periodic checks on blood potassium levels and kidney function may be performed.