Phenytoin Sodium Tablets

This product is an antiepileptic drug and antiarrhythmic 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 epileptic seizures, but ineffective for absence seizures. Its antiepileptic 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, raising the excitation threshold, and reducing the spread of high-frequency discharges in the lesions. 2 In addition, this product shortens the action potential interval and the effective refractory period, and can also inhibit the influx of calcium ions, reduce myocardial automaticity, inhibit the sympathetic center, and have an inhibitory effect on the ectopic rhythm points of the atria and ventricles, increasing the thresholds for atrial fibrillation and ventricular fibrillation. 3 Its stability

The main ingredient of this product is phenytoin sodium, and its chemical name is: 5,5-diphenyl-2,4-imidazolidinedione sodium salt

This product is white tablets or film-coated tablets.

It is suitable for the treatment of generalized tonic-clonic seizures, complex partial seizures (psychomotor seizures, temporal lobe epilepsy), simple partial seizures (localized seizures) and status epilepticus. It can also be used to treat trigeminal neuralgia, recessive dystrophic epidermolysis bullosa, paroxysmal choreoathetosis, paroxysmal control disorders (including behavioral disorders such as anger, anxiety and insomnia due to excessive excitement), myotonia and cardiac conduction disorders in case of overdose of tricyclic antidepressants. This product is also suitable for ventricular and supraventricular arrhythmias caused by digitalis poisoning, and has poor efficacy on arrhythmias caused by various other reasons.

Common dosage for anti-epileptic drugs in adults: 250-300 mg per day, 100 mg at the beginning, twice a day, increase to 250-300 mg within 1-3 weeks, divided into three times for oral administration, the maximum dose is 300 mg once, 500 mg per day. Due to individual differences and saturation pharmacokinetic characteristics, medication needs to be individualized. After the seizures are controlled and the blood drug concentration reaches a steady state, a long-acting (controlled-release) preparation can be used instead, taken all at once. If the seizures are frequent, 12-15 mg/kg can be taken according to body weight, divided into 2-3 times, once every 6 hours, and 100 mg (or 1.5-2 mg/kg according to body weight) can be given from the next day, 3 times a day until the appropriate dose is adjusted. Common dosage for children: Start with 5 mg/kg per day, divided into 2-3 times, adjust as needed, with no more than 250 mg per day.

This product has few side effects, common gingival hyperplasia, and a high incidence in children. Oral hygiene and gingival massage should be strengthened. After long-term use or when the blood drug 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 related to the dose. Common dizziness and headaches can cause nystagmus, ataxia, slurred speech and confusion in severe cases. Adjusting the dose or stopping the drug can eliminate them; less common adverse reactions of the nervous system include dizziness, insomnia, transient nervousness, twitches, chorea, dystonia, tremor, asterixis, etc. It can affect the hematopoietic system, causing granulocytopenia and thrombocytopenia, and rare aplastic anemia; common megaloblastic anemia can be prevented and treated with folic acid and vitamin B12. It can cause allergic reactions, common rashes with high fever, and rare severe skin reactions, such as exfoliative dermatitis, multiform erosive erythema, systemic lupus erythematosus and fatal liver necrosis, Hodgkin's disease of the lymphatic system, etc. Stop the drug immediately and take appropriate measures if symptoms appear. Long-term use in children can accelerate vitamin D metabolism and cause rickets or bone abnormalities. Use by pregnant women can occasionally cause teratogenesis. It can inhibit the secretion of antidiuretic hormone and insulin, causing blood sugar to rise, and there have been reports of it causing cancer.

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 poor control of 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 effective blood concentration, and then readjust it 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 many combined medications in treatment. The interactions between drugs are complex. When using this product, caution should be exercised, the dosage should be low, and blood drug concentration should be monitored frequently.

1. Long-term use of acetaminophen in patients may increase the risk of liver poisoning and reduce the efficacy. 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 and toxicity of this product; combined with anticoagulants, the anticoagulant effect will increase at the beginning, but it will decrease with continuous use. 4. When used in combination with magnesium, aluminum or calcium carbonate, the bioavailability of this product may be reduced. 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 who use dopamine should not use this product. 7. This product may enhance the inhibitory effect on the heart when used in combination with lidocaine or propranolol. 8. Although this product consumes folic acid in the body, increasing folic acid can reduce the concentration and effect of this product. 9. The effect of phenobarbital or primidone on this product varies greatly, and the blood concentration should be monitored frequently; when used in combination with valproic acid, there is a protein binding competition, and the blood concentration should be monitored frequently to adjust the dosage of this product. 10. When used in combination with carbamazepine, the latter's blood concentration is reduced. 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.

0.1g

Tentative 24 months

Kaifeng Pharmaceutical (GROUP) Co., Ltd.

• Founded in:

  2003-09-26

• Address:

  No. 1, Yunan Street, Kaifeng City

• Tax NO.:

  914102007551588773

• Registered Funds:

  204.568562 million yuan

• Email:

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