Difenin is a derivative of hydantoin, which has anticonvulsant, muscle relaxant, analgesic and antiarrhythmic effects.
Release form and composition
Difenin dosage form - tablets.
The active ingredient of the drug is phenytoin. Its concentration in a single tablet is 100 mg.
Indications for use
According to the instructions to Difenin, the drug is intended for the treatment of:
- Large convulsive seizures;
- Status epilepticus accompanied by tonic-clonic seizures;
- Myotonia, including congenital;
- Epileptic seizures in neurosurgery;
- Episodic behavioral disorders (anger, irritability, insomnia, anxiety, hyper excitability);
- Paroxysmal choreoathetosis;
- Ventricular arrhythmias, including those caused by intoxication with tricyclic antidepressants and cardiac glycosides;
- Rhythm disturbances associated with organic lesion of the central nervous system;
- Congenital long QT interval syndrome (with the ineffectiveness of beta-blockers);
- Trigeminal neuralgia (in combination with carbamazepine or as a second-line agent).
Difenin is also prescribed for prophylaxis:
- Post-neurosurgical and post-traumatic epilepsy;
- Ventricular arrhythmias after heart surgery.
The use of difenina contraindicated in:
- Hypersensitivity to phenytoin or any auxiliary component;
- Morgagni-Adams-Stokes Syndrome;
- Sinus bradycardia;
- AV blockade II-III degrees;
- Sinoauricular blockade;
- Heart failure;
- Impaired liver / kidney function;
With caution, the drug should be used in patients with alcoholism, diabetes, as well as hyperthermia and systemic lupus erythematosus.
Dosing and Administration
According to the instructions to Difenin, tablets should be taken after meals.
When prescribing the drug as an anticonvulsant and sedative, the initial single dose is 100-300 mg, the multiplicity of reception - 1-3 times a day. If necessary, it is gradually increased to the optimal maintenance dosage (usually it is 200-500 mg per day).
As an antiarrhythmic agent, Difenin is usually taken 1 tablet four times a day. For about 3-5 days, the effect of the drug appears, after which the frequency of dosing is reduced to 3 times. In order to quickly achieve the required therapeutic concentration of phenytoin, the following regimen of Difenin can be prescribed: 2 tablets 5 times during the first day, the next 2 days - 1 tablet 5 times, from 4 days of treatment - 1 table. 2-3 times a day. With this drug intake, the antiarrhythmic effect, as a rule, is achieved already on the 1-2 day of treatment.
At the beginning of therapy, children are prescribed medication at the rate of 5 mg per kilogram of weight. If necessary, increase the dose, but not more than 300 mg per day. Maintenance dosage is 4-8 mg / kg.
Patients with renal failure require a dose reduction of Difenin, sometimes by 50%.
When using Difenin, according to the instructions, the following side effects may occur:
- Confusion, ataxia, mood changes, nystagmus, muscle weakness, dizziness, impaired motor coordination, transient nervousness, trembling hands, sleep disturbances, stuttering or blurred speech, in some cases - peripheral neuropathy;
- Nausea and / or vomiting, toxic hepatitis, constipation, liver damage, gum hyperplasia, starting with gingivitis;
- Granulocytopenia, leukopenia, agranulocytosis, megaloblastic anemia, thrombocytopenia, pancytopenia;
- Hypertrichosis, expansion of the tip of the nose, thickening of the lips, the extension of the lower jaw;
- Dupuytren's contracture, in some cases - peripheral polyarthropathy;
- Violation of glucose uptake and metabolism of vitamin D, the development of hypocalcemia;
- Peyronie's Disease.
In case of hypersensitivity or intolerance of the drug, allergic reactions may develop, including fever, eosinophilia, drug lymphadenopathy and skin rash, which may be a prodromal symptom of more severe reactions, including toxic epidermal necrolysis and Stevens-Johnson syndrome.
With long-term use of Difenin and the absence of sufficient solar radiation or an adequate diet that would satisfy the need for vitamin D, osteomalacia and rickets are possible.
Patients with epilepsy during the period of withdrawal of Difenin are prescribed anticonvulsants, which do not belong to the group of hydantoin derivatives, since abrupt discontinuation of treatment may cause the development of withdrawal syndrome.
During the period of use of Difenin, especially long, it is recommended to adhere to a diet that satisfies the body's need for vitamin D.
The concentration of phenytoin in the blood can increase phenylbutazone, felbamate, diltiazem, gabapentin and cimetidine, in some cases this is accompanied by the development of a toxic effect. A decrease in the concentration of the active substance and, as a consequence, a decrease in the effectiveness of Difenin, possibly with its simultaneous use with folic acid, vigabatrin, reserpine, carbamazepine and sucralfate.
It should be borne in mind that the use of medication during the growth of children increases the risk of side effects from the connective tissue.
Phenytoin may adversely affect the speed of psychomotor reactions. This should be taken into account by people who operate vehicles and are engaged in potentially hazardous industries.
Diphentoin, Phenytoin, Epanutin, Zentropil, Dihydantoin, Alepsin, Dilantin sodium, Sodanton, Difedan, Hydantoinal, Eptoin, Solantoin, Fengidon, Solantil, Hydanthal, etc.
Terms and conditions of storage
Difenin belongs to the group of drugs sold strictly on prescription. Store the tablets should be at a temperature of from 5 to 30 ºC. Their shelf life is 4 years.