Fosipril

Fosipril - Precautions | Dosage | Effects

Fosipril is a drug containing an active substance called fosinopril. It belongs to a group of medicines called angiotensin-converting enzyme inhibitors (ACE inhibitors).

The mechanism of action of Fosipril is illustrated below:

As you can see, Fosipril reduces the formation of angiotensin II - a substance that narrows blood vessels and raises blood pressure. By reducing the concentration of this substance, Fosipril exhibits a hypotensive effect (lowering of blood pressure), but also causes reduction in cardiac overload, which is useful in the treatment of angina.

In addition, reduction in angiotensin II blood levels increases sodium excretion and reduces potassium excretion. Therefore, there is a risk of hyperkalaemia (high potassium levels), especially in patients taking potassium supplements or other drugs that increase the concentration of this mineral. Hyperkalaemia can cause cardiac arrhythmias which can be life-threatening!

It is also presumed that Fosipril inhibits the deactivation of bradykinin (a substance that widens blood vessels), and increases its blood concentration, which further contributes to the hypotensive effect. However, this mechanism has yet to be proven.

Fosipril is indicated for the treatment of hypertension and cardiac failure.

Precautions

Cases of cholestatic jaundice have been reported with this drug, therefore it is necessary to administer Fosipril with extra precaution in patients who have impaired liver function. Patients with impaired liver function may have elevated levels of fosinopril in the blood, because this drug is primarily metabolized through the liver.

The use of Fosipril is contraindicated in patients with renal artery stenosis on one or both kidneys. Studies have shown that Fosipril reduces the degree of glomerular filtration (GFR) and causes functional renal impairment in patients with renal stenosis.

Fosipril should be used with caution in patients with decompensated cardiac failure.

Fosipril is absolutely contraindicated in patients with cardiogenic shock as well as in pregnant women in the second and third trimester of pregnancy.

Fosipril should be used with extra precaution in the following situations:

  • In patients with impaired renal function.
  • In diabetics.
  • In patients with enlarged heart muscle (a condition called cardiomyopathy).
  • In patients who have electrolyte imbalances (e.g. due to dehydration or a diet).
  • In patients with autoimmune diseases (e.g. systemic lupus).

Fosipril and its use during pregnancy and lactation

The use of Fosipril tablets during the second or third trimester increases the risk of fetal and neonatal death, which is why its use in this period is absolutely contraindicated (FDA Pregnancy Category D). Its use during the first trimester of pregnancy should also be avoided (FDA Pregnancy Category C).

It should not be used in nursing mothers because it is excreted into breast milk.

Dosage instructions

The usual starting dose in the treatment of hypertension and cardiac failure is 10mg once a day. The dose may be increased up to 40mg daily, which is the maximum daily dose.

In patients with heart failure, who have moderate or severe impairment of renal function, it is recommended to use a lower initial dose (5mg once a day).

Fosipril can be combined with diuretics as well as with digoxin in cardiac failure therapy.

Food has no effect on the absorption of the active substance, so you can take tablets before or after a meal.

According to the FDA, doses between 0.1-0.6 mg/kg of body weight have shown antihypertensive effects in children, so the recommended dose in children with hypertension weighing more than 50kg is 5-10mg once daily.

However, the manufacturer does not recommend the use of this medicine in children because the safety and efficacy of this drug in children has not been established yet.

Interactions

Fosipril should not be administered concurrently with the following medicines:

  • Direct renin inhibitors, such as aliskiren (used to treat hypertension). Simultaneous administration increases the risk of kidney damage and hyperkalaemia.
  • Allopurinol - a medicine used to treat gout. Simultaneous administration increases the risk of allergic reactions.
  • Sulfomethoxazole / trimethoprim (commonly known as Bactrim) - a medicine used to treat infections, most commonly urinary infections. Simultaneous administration increases the risk of hyperkalaemia.
  • Potassium supplements.
  • Potassium-sparing diuretics, such as: triamterene, spironolactone and amiloride.
  • Angiotensin II-receptor blockers, such as: irbesartan, valsartan, candesartan, losartan, and others. These drugs are used to treat hypertension. Simultaneous administration increases the risk of kidney damage and hyperkalaemia.
  • Tizanidine (muscle relaxant).
  • Lithium - antipsychotic. Fosipril increases lithium levels in the blood, thus increasing the risk of side effects. Simultaneous administration should be carried out only under strict medical supervision along with frequent monitoring of lithium concentration in the blood.
  • Antacids - medicines used to treat heartburn, such as: aluminum hydroxide, magnesium hydroxide and symethicone. These drugs reduce the absorption of Fosipril, which can affect its effectiveness.
  • Immunosuppressants, such as: leflunomide and azathioprine. Simultaneous administration with these medicines can affect the white blood cell count.
  • Non-steroidal anti-inflammatory drugs, such as: acetylsalicylic acid (Aspirin), diclofenac, indomethacin, ibuprofen, ketoprofen, sulindac, and others. These medicines can reduce the efficacy of Fosipril.
  • Medicines used to treat diabetes. Fosipril may increase the effect of these drugs, so dosage adjustment is necessary.

Tell your doctor about all the medicines you are taking.

Adverse effects

Fosipril may cause the following side effects:

  • Dry cough (occurs very often).
  • Palpitations.
  • Tachycardia (rapid heart rate).
  • Dizziness.
  • Orthostatic hypotension.
  • Chest pain.
  • Angina.
  • Heart attack.
  • Decreased libido.
  • Inflammation of the joints.
  • Inflammation of the muscles.
  • Upper respiratory tract infections (sinusitis, pharyngitis, laryngitis and rhinitis).
  • Pneumonia.
  • Stuffy or runny nose.
  • Blurred vision.
  • Increased sweating.
  • Stuffy ear.
  • Decrease in blood sodium levels.
  • Increase in blood potassium levels.
  • Arrhythmias.
  • Angioedema.
  • Dermatitis.
  • Insomnia.

Tell your doctor if you are experiencing any adverse effects.

References

  1. FDA
  2. NCBI link 1
  3. NCBI link 2

Information on this website are provided for educational purposes only and are not intended for medical advice, diagnosis or treatment.

If you have any concerns or questions about your health, you should always consult with a physician or other health-care professional.