The "tartaric acid" and "succinic acid" of metoprolol have similar effects, but the methods of administration are different.

Many friends asked Huazi, there are two types of metoprolol, one is "metoprolol tartrate" and the other is "metoprolol succinate". The "acid" in front of the drug names is different. What is the difference? Are there any differences in the efficacy?

Hua Zi said that metoprolol is a commonly used beta-blocker that can lower heart rate and blood pressure and reduce myocardial oxygen consumption. Although there is a difference between "tartaric acid" and "succinic acid" before the drug name, in fact, both are metoprolol and have basically the same efficacy. The two are mainly different in the duration of action and the way of taking them.

1. Adding "acid" makes it more stable. Careful friends will find that many drugs contain various acids, such as hydrochloric acid, sulfuric acid, benzenesulfonic acid, tartaric acid, succinic acid, etc., the purpose of which is to combine with weakly alkaline drugs to form salts. Weakly acidic drugs combine with alkaline ions to form salts. Because many drug monomers are unstable under natural conditions, they can only exist stably after forming salts.

After the drug is salted, it not only increases stability, but also increases solubility. After taking it, it will dissociate into simple drugs in the human body to exert its effects. The same is true for metoprolol. However, different acids form salts at different dissociation rates. In comparison, metoprolol tartaric acid dissociates faster, while metoprolol succinate dissociates slower.

2. The difference in release rate between the two can also be seen in the names of the drugs, which are "Metoprolol Tartrate Tablets" and "Metoprolol Succinate Sustained Release Tablets". The former is a common tablet, which is quickly absorbed after taking and reaches the peak blood concentration. The half-life is about 3 to 5 hours. Usually 2 to 4 doses a day are required to maintain effective blood concentration. It can be used for patients who need to quickly control heart rate and blood pressure.

Metoprolol succinate sustained-release tablets are long-acting sustained-release preparations. After taking them, the drug is slowly released at an almost constant rate, and the duration of the drug effect is about 20 hours, so it can be taken once a day. It is often used for patients with hypertension, coronary heart disease, etc. who need to take long-term medication. The drug is slowly released, has a mild effect, and has fewer side effects.

3. Differences in the way of taking Metoprolol tartrate can be broken into pieces and taken. People who have difficulty swallowing can also grind it into powder or chew it before taking it, which will not affect its efficacy. However, metoprolol succinate sustained-release tablets use microcapsule sustained-release technology and can be broken along the score line for taking, but cannot be ground or chewed before taking.

When metoprolol tartrate is taken with food, the absorption rate will increase by 40%, causing drastic fluctuations in blood pressure and increasing adverse reactions, so it should be taken 30 minutes before meals or 2 hours after meals. However, the sustained-release microcapsules of metoprolol succinate sustained-release tablets are not affected by diet, so they can be taken before or after meals.

IV. Dosage and side effects Due to the different qualities of tartaric acid and succinic acid, the dosage of the two is slightly different when used. The dosage of 50 mg of metoprolol tartrate tablets is equivalent to that of 47.5 mg of metoprolol succinate sustained-release tablets.

In terms of side effects and contraindications, the two are basically the same. Both may cause a decrease in heart rate, low blood pressure, cold limbs, and Raynaud's syndrome. Therefore, people with bradycardia and atrioventricular block should not use it. Common side effects are central nervous system symptoms such as fatigue, dizziness, and headache, as well as gastrointestinal reactions such as nausea and vomiting, but they generally do not affect medication. Since the drug release rate of metoprolol succinate sustained-release tablets is slower, there are fewer adverse reactions.

Long-term use of metoprolol will increase the response of beta receptors on the heart. If the drug is stopped suddenly, there may be a "drug withdrawal rebound" phenomenon, causing a sudden increase in blood pressure and tachycardia, which may induce cardiovascular and cerebrovascular diseases. Therefore, when it is necessary to stop the drug, it is necessary to go through a process of gradual reduction and discontinuation of the drug for about 2 weeks.

In summary, metoprolol tartrate tablets and metoprolol succinate sustained-release tablets are very similar in efficacy, and the main difference is in the way of taking them. There are also some generic drugs for metoprolol tartrate sustained-release tablets, which have an action time between the two and need to be taken twice a day. The specific usage should be based on the instructions. The drug must be used under the guidance of a doctor. If you have any questions about the use of the drug, please consult a doctor or pharmacist in time. I am pharmacist Huazi, welcome to follow me and share more health knowledge.