Products
Metoprolol is commercially available as sustained-release tablets and as a solution for injection (Beloc ZOK, Lopresor, generics). It has been approved in many countries since 1975.
Structure and properties
Metoprolol (C15H25NO3, Mr = 267.36 g/mol) is a racemate. It is present in drugs in the form of the salts metoprolol succinate or metoprolol tartrate. They are white crystalline powders that are readily soluble in water.
Effects
Metoprolol (ATC C07AB02, ATC C07AB02) is a cardioselective β1-beta blocker. It lowers blood pressure, regulates heart rate, and is antianginal and antiarrhythmic. It is not membrane stabilizing and lacks partial agonist activity. A special galenics of the tablets allows the release of the active substance for 20 hours. Thus, despite a short half-life of 3.5 hours, once-daily administration is sufficient.
Indications
- High blood pressure
- Angina pectoris
- Chronic heart failure
- Cardiac arrhythmias
- Migraine prophylaxis
Dosage
According to the professional information. The sustained-release tablets are taken once daily with a glass of water. The intake is independent of meals. Some of the sustained-release tablets are divisible. However, they should not be chewed or crushed.
Contraindications and interactions
Full and comprehensive information on contraindications and interactions can be found in the drug label. Metoporol is degraded by CYP2D6 to inactive metabolites and appropriate interactions are possible.
Adverse effects
The most common possible adverse effects include dizziness, headache, deep pulse, orthostatic disturbances, cold hands and feet, palpable heartbeats, exertional dyspnea, nausea, pain, diarrhea, and constipation. Several other side effects may occur.
