Phenytoin Sodium Tablets

It is an anti-epileptic drug and anti-arrhythmic drug. The therapeutic dose does not cause sedation and hypnosis. 1. Animal experiments have shown that this product has a selective antagonistic effect on the tonic phase of super-strong electric shock and convulsion, but is ineffective or even aggravates the spasm phase. Therefore, it is effective for grand mal epilepsy, but ineffective for absence seizures. Its anti-epileptic mechanism has not yet been elucidated. It is generally believed that it increases the outflow of sodium ions from cells and reduces the inflow of sodium ions, thereby stabilizing the nerve cell membrane, increasing the excitation threshold, and reducing the spread of high-frequency discharges in the lesion. 2. In addition, this product shortens the action potential interval and effective refractory period, and can also inhibit the inflow of calcium ions, reduce myocardial autonomicity, inhibit the sympathetic center, and have an inhibitory effect on the ectopic rhythm points of the atrium and ventricle, and increase the threshold of atrial fibrillation and ventricular fibrillation. 3. Its cell membrane stabilization effect and reduced synaptic transmission have anti-neuralgia and skeletal muscle relaxation effects. 4. This product can inhibit the synthesis (or) secretion of collagenase by skin fibroblasts. It can also accelerate the metabolism of vitamin D, cause lymphadenopathy, have anti-folate effects, have inhibitory effects on the hematopoietic system, cause allergic reactions, have enzyme-inducing effects, and intravenous administration can dilate peripheral blood vessels.

The main ingredient of this product is phenytoin sodium, its chemical name is: 5,5-diphenyl-2,4-imidazolidinedione sodium salt, chemical structure formula is: Molecular formula: C15H11N2NaO2 Molecular weight: 274.25

This product is white tablets or film-coated tablets.

The main indications of this product are various supraventricular and ventricular arrhythmias that occur during digitalis poisoning; congenital long QT syndrome; arrhythmias that occur in epileptic patients, etc.

The usual dosage is 50-100 mg orally at a time and 100-300 mg per day. The maximum dosage is 300 mg orally at a time and 500 mg per day.

This product has few side effects, and gingival hyperplasia is common. The incidence rate is high in children, so oral hygiene and gingival massage should be strengthened. After long-term use or when the blood concentration reaches 30mu;g/ml, it may cause nausea, vomiting and even gastritis, which can be alleviated by taking it after meals. Adverse reactions of the nervous system are dose-related, and common ones include dizziness and headache. In severe cases, they may cause nystagmus, ataxia, slurred speech and confusion, which can disappear by adjusting the dose or stopping the drug; less common adverse reactions of the nervous system include dizziness, insomnia, transient nervousness, convulsions, chorea, dystonia, tremor, flapping tremor, etc. It can affect the hematopoietic system, causing granulocytopenia and thrombocytopenia, and rare aplastic anemia; megaloblastic anemia is common, which can be prevented and treated with folic acid and vitamin B12. It can cause allergic reactions, common rash with high fever, and rare severe skin reactions.

Contraindications: Patients with a history of allergy to hydantoins or those with heart function impairment such as Ass syndrome, II-III degree atrioventricular block, sinus node block, sinus bradycardia, etc.

Precautions for children: Since the distribution volume and elimination half-life of children change with age, blood drug concentration should be measured frequently. The pharmacokinetics of this product are special for neonates or infants, and it is difficult to evaluate the symptoms of poisoning clinically, so it is generally not used first. Preschool children have strong liver metabolism, and blood drug concentration needs to be monitored multiple times to determine the frequency and dosage of medication. Precautions for pregnancy and lactation: This product can pass through the placenta and may cause teratogenesis, but it is believed that the risk of teratogenesis due to uncontrolled epileptic seizures is greater than the risk of medication, and the pros and cons should be weighed. Patients who can control seizures with this product should continue to take it during pregnancy and maintain blood concentration, and then readjust after delivery. Vitamin K should be supplemented one month before delivery, and vitamin K should be injected into the newborn immediately after delivery to reduce the risk of bleeding. This product can be secreted into breast milk, and it is generally recommended that mothers taking phenytoin sodium avoid breastfeeding. Precautions for the elderly: The incidence of chronic hypoproteinemia in the elderly is high, and there are more combined medications in treatment, and the interactions between drugs are complex. Be cautious when using this product, and the dosage should be low. And monitor blood drug concentration frequently.

① Long-term use of acetaminophen in patients may increase the risk of liver poisoning and reduce the efficacy of this product; ② It is a liver enzyme inducer. When used in combination with corticosteroids, digitalis (including digoxin), oral contraceptives, cyclosporine, estrogen, levodopa, quinidine, oxytetracycline or tricyclic antidepressants, the effects of these drugs may be reduced; ③ Long-term drinking can reduce the concentration and efficacy of this product, but drinking a lot of alcohol while taking the medicine can increase the blood concentration; combined with chloramphenicol, isoniazid, phenylbutazone, and sulfonamides may reduce the metabolism of this product and increase the blood concentration, increasing the toxicity of this product; when used in combination with anticoagulants, the anticoagulant effect is initially increased, but it is reduced with continuous use; ④ When used in combination with drugs containing magnesium, aluminum or calcium carbonate, the bioavailability of this product may be reduced, and the two should be taken 2 to 3 hours apart; ⑤ When used in combination with hypoglycemic drugs or insulin, because this product can increase blood sugar, the dosage of the latter two needs to be adjusted; ⑥ In principle, patients using dopamine should not use this product; ⑦ When this product is used in combination with lidocaine or propranolol, it may enhance the inhibitory effect on the heart; ⑧ Although this product consumes folic acid in the body, increasing folic acid can reduce the concentration and effect of this product; ⑨ The effects of phenobarbital or primidone on this product vary greatly, and blood drug concentrations should be monitored frequently; when used in combination with valproic acid, there is a protein binding competition, and blood drug concentrations should be monitored frequently to adjust the dosage of this product. ⑩ When used in combination with carbamazepine, the latter has a lower blood concentration. If a large amount of antipsychotics or tricyclic antidepressants are used in combination, epileptic seizures may occur, and the dosage of this product needs to be adjusted.

Keep away from light and store in airtight container.

50mg

36 months

Shanxi Fenhe Pharmaceutical Co., Ltd.

• Founded in:

  2003-12-24

• Address:

  Dongwang, Jiefang East Road, Linfen City

• Tax NO.:

  91141000757261333L

• Registered Funds:

  38 million yuan

• Email:

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