Metoprolol lowers heart rate, will it cause insufficient blood supply? What are the precautions?

Metoprolol is a commonly used antihypertensive drug in the treatment of hypertension. People often ask Huazi, I heard that metoprolol can reduce heart rate. If the heartbeat slows down, will the blood supply to the body be reduced? What should I do if there is insufficient blood supply? How can people with high blood pressure use it safely?

Huazi replied that, under normal circumstances, taking metoprolol will not cause insufficient blood supply to important organs of the body. However, when hypertensive patients use metoprolol, they need to measure their heart rate, and those with too low a heart rate should not use it.

1. Antihypertensive drugs that give the heart more rest Metoprolol, a type of leptin drug, is a highly selective β1 receptor blocker that can block β1 receptors on the heart, inhibit over-activated sympathetic nerve activity, inhibit myocardial contractility, slow heart rate, and reduce cardiac output; it can also inhibit β1 receptors on juxtaglomerular cells and reduce renin secretion. Blood pressure is lowered through two pathways.

In other words, the role of metoprolol is to give the overexcited heart "more rest", and while lowering blood pressure, it can also protect the heart well. It is especially suitable for hypertensive patients with heart diseases such as tachyarrhythmia, coronary heart disease, and chronic heart failure. It is also often used for hypertension caused by increased sympathetic nerve activity in young and middle-aged people.

2. Will Metoprolol cause insufficient blood supply? Metoprolol inhibits excessive excitability of the heart and reduces cardiac output, but generally does not affect normal blood supply. However, when a large dose is used and the heart rate is too low, cardiac output drops sharply, which may cause adverse reactions such as palpitations, bradycardia, and cold limbs.

Before using metoprolol, you need to measure your resting heart rate. It is only suitable to use it if it is greater than 80 beats per minute. Start with a small dose and gradually increase the dose. Monitor your heart rate during medication. Hypertensive patients can control their heart rate between 60 and 70, and patients with coronary heart disease can control their heart rate between 55 and 60. The lowest heart rate should not be lower than 55.

3. The difference between "Metoprolol Tartrate" and "Metoprolol Succinate" Commonly used metoprolol has two dosage forms: metoprolol tartrate tablets and metoprolol succinate sustained-release tablets. Metoprolol tartrate is a common preparation with rapid oral absorption and short duration of action. It needs to be taken twice a day. Food will increase drug absorption and there is a risk of causing blood pressure fluctuations and bradycardia, so it needs to be taken on an empty stomach half an hour before meals.

Metoprolol succinate sustained-release tablets are long-acting preparations. The drug is slowly released through microcapsule sustained-release technology, so the tablets can be broken apart and taken without affecting the sustained-release effect, but they cannot be crushed or chewed. The drug is taken once a day, regardless of diet, and is usually taken in the early morning.

4. Adverse reactions and withdrawal syndrome of metoprolol When taking metoprolol, gastrointestinal reactions such as abdominal pain, nausea, vomiting, and constipation may occur, but the symptoms are usually mild and tolerable. Metoprolol is highly lipid-soluble and easily enters the central nervous system, causing adverse reactions such as headache and dizziness. If the symptoms are severe, you can consider replacing it with atenolol, a highly water-soluble β1 receptor blocker.

Long-term use of metoprolol may occasionally cause erectile dysfunction (ED) in men, but studies have shown that this side effect only occurs in non-selective olamine drugs. Metoprolol is highly selective for β1 receptors, and the cause of ED is not related to drugs. Most patients suffer from psychological factors. However, for patients with severe symptoms, bisoprolol, which is more selective for β1 receptors, can be considered as a substitute.

During medication, the heart rate should be monitored and the minimum heart rate should be kept above 55. Metoprolol is a highly selective β1 receptor blocker and generally does not inhibit β2 receptors on the bronchus. However, people with asthma should use metoprolol with caution. If symptoms of dyspnea occur, it can be used together with bronchodilators.

Metoprolol can affect glucose and lipid metabolism, but its benefits in treating cardiovascular disease and hypertension far outweigh its effects on glucose and lipids. Therefore, patients with diabetes and hyperlipidemia can take it, but during treatment, they should pay attention to monitoring blood sugar and blood lipids, and adjust the corresponding dosage of glucose-lowering and lipid-lowering drugs.

When metoprolol is used for a long time, the heart will compensate by increasing the number of β1 receptors due to the continuous inhibition of β1 receptors on the heart. If the drug is stopped suddenly, "withdrawal syndrome" will occur, manifested as anxiety, restlessness, palpitations, increased blood pressure, tachycardia, angina pectoris and other symptoms, and in severe cases, myocardial infarction may be induced. Therefore, long-term users who need to stop the drug must use a doctor's guidance and slowly reduce the dosage for no less than 2 weeks before stopping the drug.

In summary, when using metoprolol, you need to monitor your heart rate. As long as your heart rate is not too low, there will usually be no insufficient blood supply. During use, if adverse reactions occur, you should communicate with your doctor and use alternative drugs or other drugs to counteract them under the guidance of your doctor. Also, be careful not to stop taking the drug suddenly. I am pharmacist Huazi. Welcome to follow me and share more health knowledge.