What is the difference between metoprolol tartrate and metoprolol succinate?😵😵😵

Metoprolol is a commonly used selective β1 receptor blocker in clinical. It is
mainly used to treat cardiovascular related diseases such as hypertension, hyperthyroidism, myocardial infarction, angina pectoris, arrhythmia and heart failure. In currently clinical, there are two dosage forms. They are metoprolol tartrate tablets and metoprolol succinate sustained-release tablets. Although they are both metoprolol, they are different dosage forms and have different administration methods.

1. Indications

Since they are both Metoprolol, their indications are basically the same. They can be used to treat myocardial infarction, angina pectoris, arrhythmia, cardiomyopathy, hypertension, heart failure and so on. 

For patients who need to stably control blood pressure and treat heart disease for long-term, metoprolol sustained-release tablets have more advantages than ordinary tablets.

2. Dosage difference

Metoprolol tartrate is an ordinary tablet. The drug can be completely disintegrated after it entering the body. The blood concentration will quickly achieve the peak value and result in a systemic effect. However, the ordinary tablet will remove quickly in the body. So it has a short half-life. The effect of ordinary tablets will not be destroyed by breaking or crushing. Therefore, it can be broken or crushed for taking.

The sustained-release dosage form of metoprolol succinate is composed of many microencapsulated particles. Each particle is wrapped with a polymer film to form an independent storage unit to control the release rate of the drug. Therefore, metoprolol succinate sustained-release tablets are different from other sustained-release tablets. If it is necessary, the tablets can be broken apart to increase dosage. But it cannot grind or chew tablets. the microcapsule particles will be destroyed by grinding or chewing. It will causes all the drugs in the microcapsules are released immediately. It will increase the medical effects greatly and aggravate adverse effects.

3. Administration methods

The half-life of metoprolol tartrate tablets is 3-5 hours. Therefore, the commonly used clinical dose is 2-4 times a day.

Metoprolol succinate sustained-release tablets are released in the body at a nearly constant rate for about 20 hours. The blood concentration is stable and the effect exceeds 24 hours. Therefore, it only needs to be taken once a day. It is recommended to take it in the morning.

4. Food

Metoprolol tartrate tablets are fat-soluble drugs. Food can affect their absorption. If the drug is took with meals, it can greatly increase the bioavailability of the drug by 40% and increase the incidence of side effects such as bradycardia. Therefore, in order to avoid the increase of adverse drug events, the drug should be taken on an empty stomach.

The release of metoprolol succinate sustained-release tablets is not affected by the pH value in the stomach and the intake of food does not affect its bioavailability either. Therefore, the drug can be taken before or after meals. However, the drug should be took by at least half a glass of water.

5. Contraindications

Their contraindications are also basically the same.

• Cardiogenic shock
• Unstable/decompensated heart failure
• II, III degree atrioventricular block
• Sick sinus syndrome
• Severe peripheral vascular disease with risk of gangrene
• Metoprolol allergy
• Bradycardia 
• Low blood pressure
• Suspected acute myocardial infarction patients with heart rate < 45 beats/min, P-Q interval > 0.24 seconds or systolic blood pressure <100 mmHg

👉It is necessary to pay attention to the different usage methods of the two dosage forms. It should be avoided the unnecessary adverse reactions.