Who can tell me something about the medicinal knowledge of aquatic medicine aminophylline?

Generic name: aminophylline sustained-release tablets

Name used:

Product name:

English name: aminophylline sustained-release tablets

Hanyu Pinyin: An Cha Jian Huan Shi Pian

The main component and chemical name of this product are: aminophylline is the main component of this product, and the chemical name is 1, 3- dimethyl-3,7-dihydro-1H- purine-2,6-dione-1, 2- ethylenediamine dihydrate.

Its structural formula is:

Molecular formula: C2H8N2(C7H8N4O2)2? 2H2O

Molecular weight: 456.46

Character; Role; letter

This product is a white or yellowish film-coated tablet.

pharmacological action

This product is a double salt of theophylline and ethylenediamine, and its pharmacological action mainly comes from theophylline, and ethylenediamine enhances its water solubility. This product has a direct relaxing effect on respiratory smooth muscle. Its mechanism is complicated, and it is thought that it can increase the content of cAMP in cells by inhibiting phosphodiesterase. Recent experiments show that the bronchodilatory effect of theophylline is partly due to the release of endogenous epinephrine and norepinephrine. In addition, theophylline is a purine receptor blocker, which can resist the contraction of adenine on respiratory tract. Theophylline can enhance diaphragm contractility, especially when diaphragm contractility is weak, so it is beneficial to improve respiratory function.

pharmacokinetics

This product can be absorbed slowly by oral administration. In vivo aminophylline releases theophylline, and the protein binding rate of the latter is 60%. T 1/2 newborns (within 6 months) > 24 hours, children (over 6 months) 3.7 hours 1. 1 hour, adults (non-smokers and asthma-free) 8.7 hours and 2.2 hours, smokers (smoking 1-2 packs a day) Most of this product is excreted through the kidney in the form of metabolites, and 10% is excreted in its original form.

adapt to

It is suitable for relieving asthmatic symptoms such as bronchial asthma, asthmatic bronchitis and obstructive emphysema. It can also be used for asthma caused by cardiogenic pulmonary edema.

dosage

1. Adults generally take 0. 1g( 1 tablet) ~0.2g(2 tablets) at a time, and 0.3g(3 tablets) ~0.6 g(6 tablets) a day; Maximum: 0.5 g once, one day1g.

2. Children generally take it orally, 3-5mg/kg each time, 3 times a day.

counteraction

The toxicity of theophylline often appears in the blood concentration 15-20μg/ml, especially in the initial stage of treatment. Nausea, vomiting, irritability and insomnia are common in the early stage. When the serum concentration exceeds 20μg/ml, tachycardia and arrhythmia may occur, and when theophylline in the serum exceeds 40μg/ml, it may cause symptoms such as fever, dehydration and convulsion, and even appear in severe cases.

Contraindications

Patients who are allergic to this product, patients with active peptic ulcer and patients with uncontrollable convulsive diseases are prohibited.

Matters needing attention

1. Like other theophylline sustained-release preparations, this product is not suitable for patients with persistent asthma or acute bronchospasm.

2. Serum theophylline concentration should be monitored regularly to ensure the maximum curative effect without the risk of high blood drug concentration.

3. Patients with renal or liver dysfunction, especially men over 55 years old and patients with chronic lung diseases, patients with heart failure caused by any cause, and patients with persistent fever. The maintenance time of serum theophylline concentration is often significantly prolonged in patients who use certain drugs and patients whose theophylline clearance rate is reduced after stopping using combined drugs. The dosage should be adjusted appropriately or the interval time should be extended.

4. Theophylline preparation can cause arrhythmia and/or aggravate the original arrhythmia; Any changes in the patient's heart rate and/or rhythm should be monitored and studied.

5. Use this product with caution in patients with hypoxemia, hypertension or digestive tract ulcer.

Medication for pregnant and lactating women

This product can pass through the placental barrier or be secreted into the milk and excreted with the milk. Pregnant women, lying-in women and lactating women should use it with caution.

Children's medication

The neonatal plasma clearance rate can be reduced, and the serum concentration can be increased, so use it with caution.

Medication for elderly patients

Use with caution in elderly patients over 55 years old, because the plasma clearance rate decreases and the potential toxicity increases.

drug interaction

1. Diltiazem and verapamil can interfere with the metabolism of theophylline in the liver, and the combination with this product can increase the blood concentration and toxicity of this product.

2. Cimetidine can reduce the liver clearance rate of this product, and increase the serum concentration and/or toxicity when combined with theophylline.

3. Some antibacterial drugs, such as erythromycin, roxithromycin, clarithromycin, enoxacin, ciprofloxacin, ofloxacin, levofloxacin, clindamycin and lincomycin, can reduce the clearance rate of theophylline and increase its blood concentration, especially erythromycin and enoxacin. When theophylline is combined with the above drugs, it should be reduced appropriately.

4. Phenobarbital, phenytoin and rifampicin can induce liver drug enzymes and accelerate the liver clearance rate of theophylline; Theophylline also interferes with the absorption of phenytoin, and the blood concentration of both drugs decreases, so the dosage should be adjusted when combined.

5. Combined with lithium salt, it can increase the renal excretion of lithium. Affect the function of lithium salt.

6. Combined with mexiletine, it can reduce the clearance rate of theophylline and increase the concentration of theophylline in plasma, so it is necessary to adjust the dose.

7. Combined with caffeine or other xanthines, it can increase its function and toxicity.

excessive

measure

0. 1 g

Storage; stock

Shading, sealing and storage.