Metoprolol (a beta-blocker)

Metoprolol has two common trade names, Lopressor and Toprol XL ( Metoprolol being the generic name ). This drug is widely used for managing chronic but stable angina i.e. when the hearts demand for oxygen exceeds the supply of oxygen reaching the heart. It has proved successful in reducing mortality due to cardiovascular diseases such as MI. The drug works essentially by blocking beta-1 receptors using an adrenergic blocker; this has the effect of slowing down the sinus heart rate. It also reduces the force of the heart muscle contraction and thus oxygen demand. This in turn lowers the cardiac output and there is a decrease in the rennin released from the kidney. In Laymans’ terms, metoprolol will bring effective relief from chest pain / tightness and high blood pressure and associated effects.

Research in the US has concluded that Metoprolol may be an effective treatment in young children with severe CHF (congestive heart failure) who are under consideration for heart transplantation. Further study is needed to better define which children benefit most from beta-blocker therapy and which beta-blockers are most beneficial, comment the researchers. Within the study of four children, the two youngest improved considerably, one went through a heart transplantion and one died.

Some side effects associated with this drug are frequent dizziness and tiredness. Occasional depression, itching and a possible rash.

Less common effects would be hypotension, palpitations, diarrhea, heartburn and on occasions, nausea. The drug is stored in an air tight container at room temperature. Metoprolol is consumed after meals or just before bedtime.

Metoprolol is widely distributed throughout the body and crosses brain and placenta barriers – for this reason, manufacturers warn against use during pregnancy ( it is classified as a pregnancy category C drug ) and breast feeding . The drug is not extensively bound to the plasma proteins but even so, the effects can be felt for up to thirty days after consumption; this is probably due to extensive tissue binding.

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