Uses of nifedipine
Nifedipine belongs to a group of medicines called calcium channel blockers. It treats high blood pressure and angina (chest pain).
Mechanism of action
Nifedipine reduces arterial smooth muscle contractility and subsequent vasoconstriction by inhibiting the influx of calcium ions through the L-type calcium channels. The calcium ions entering the cell through these channels bind to the calmodulin. Calcium-bound calmodulin binds and activates myosin light chain kinase (MLCK). Activated MLCK catalyzes the phosphorylation of the myosin light chain regulatory subunit, a critical step in muscle contraction. Signal enhancement is achieved by releasing calcium-induced by sarcoplasmic reticulum ryanodine receptors. Inhibition of initial calcium influx inhibits smooth muscle cell contractile processes, causes dilation of coronary and systemic arteries, increases myocardial tissue oxygenation, decreases overall peripheral resistance, lowers systemic blood pressure, and reduces afterload. The vasodilatory effects of nifedipine cause a general decrease in blood pressure.
The most common side effects that may occur are:
- A headache
- Redness (redness of the skin)
- Muscle cramps
- A cough
- The decreased ability or sexual desire
- Edema (swelling in the legs or feet)
Serious side effects include:
- Edema (fluid retention).
- Allergic reaction
- Low blood pressure or low heart rate
- Liver damage
- Chest pain (angina) that is worse or more common
Nifedipine in pregnancy
Nifedipine should not be used generally during pregnancy as its safety is not yet fully assured.
It is sometimes used to control high blood pressure during pregnancy. In this case, the potential risks of nifedipine in the unborn child must be weighed against the potential risk of uncontrolled maternal hypertension. Your doctor, pharmacist, or midwife may give you more information and advice on the possible effects of nifedipine on your baby and the risks associated with the treatment of high blood pressure
The usual dose for the treatment of angina is 10 to 20 mg three times a day. Up to 20 to 30 mg may be required every 6-8 hours daily. The dose should not exceed 180 mg daily. For prolonged-release tablets, the usual dose is 30 or 60 mg once daily. The maximum dose is 120 mg daily.
Hypertension is treated with 30-60 mg daily using prolonged-release tablets. The maximum dose is 90 mg / day or 120 mg / day .