It is an anticonvulsant that is used in a wide variety of attacks. It is also an antiarrhythmic and a muscle relaxant.
The mechanism of therapeutic action is unclear, although several cellular actions have been described that include effects on ion channels , active transport and general membrane stabilization.
The mechanism of its muscle relaxant effect seems to imply a reduction in the sensitivity of the muscle spindles to stretch.
Epamin has been proposed for several other therapeutic uses, but its use has been limited by its many adverse effects and interactions with other medications.
Pharmacology of Epamin
Epamin is a medication that may be useful in the treatment of epilepsy . The main site of action seems to be the motor cortex where the spread of seizure activity is inhibited.
It reduces the maximum activity of the brainstem centers responsible for the tonic phase of tonic-clonic seizures.
This medicine acts to dampen the unwanted and uncontrolled brain activity seen in seizures by reducing the electrical conductance between brain cells.
It lacks the sedative effects associated with phenobarbital . There are some indications that phenytoin has other effects, including the control of anxiety and mood stabilization, although it has never been approved for these purposes by the FDA.
Patients taking Epamin should be informed of the importance of strictly following the prescribed dosage regimen, and of informing the physician of any clinical condition in which it is not possible to take Epamin orally as prescribed, eg surgery, etc. .
Patients should also be warned about the use of other drugs or alcoholic beverages without first consulting their doctor.
Patients should be instructed to call their doctor if a rash develops.
The importance of good dental hygiene should be emphasized to minimize the development of gingival hyperplasia and its complications.
Do not use Epamin capsules that are discolored.
There are many medications that can increase or decrease phenytoin levels . Determinations of serum phenytoin level are especially useful when possible drug interactions are suspected.
Increased levels of serum phenytoin : high amounts of alcohol intake, amiodarone, chloramphenicol, chlordiazepoxide, diazepam, dicumarol, disulfiram, estrogens, H 2 -antagonists, halothane, isoniazid, methylphenidate, phenothiazines, phenylbutazone, salicylates, succinimides, sulfonamides, tolbutamide , trazodone.
Decrease in serum phenytoin levels : carbamazepine, chronic alcohol abuse, reserpine and sucralfate. The Moban brand of molindone hydrochloride contains calcium ions that interfere with the absorption of phenytoin.
The ingestion times of phenytoin preparations and calcium-containing antacids should be staggered in patients with low levels of serum phenytoin to avoid absorption problems.
Other medications that can increase or decrease serum phenytoin levels : phenobarbital, sodium valproate and valproic acid. Similarly, the effect of phenytoin on serum levels of phenobarbital, valproic acid and sodium valproate is unpredictable.
Tricyclic antidepressants : although it is not a true pharmacological interaction, tricyclic antidepressants can precipitate seizures in susceptible patients and it may be necessary to adjust the dose of phenytoin.
Medications whose efficacy is affected by phenytoin include: corticosteroids, coumarin anticoagulants, digitoxin, doxycycline, estrogens, furosemide, oral contraceptives, quinidine, rifampicin, theophylline, vitamin D.
Laboratory interaction test
Phenytoin can cause a decrease in serum levels of protein-bound iodine (PBI). It can also produce lower than normal values for dexamethasone or metyrapone tests.
Phenytoin can cause increased serum glucose, alkaline phosphatase and gamma glutamyl transpeptidase (GGT) levels.
Seek emergency medical attention if you have any of these symptoms of an allergic reaction:
- Difficult breathing
- Swelling of your face, lips, tongue or throat.
You are more likely to have an allergic reaction if you are African American.
If you have a new symptom, tell your doctor. As changes in behavior and mood, panic attacks, anxiety, insomnia, irritability, you feel agitated, restless, aggressive, depressed or have thoughts of suicide.
Contact your doctor immediately if you present:
- Fever, swollen glands, sore throat, shortness of breath, painful sores in the mouth, sores around the eyes.
- Skin rash, bruising or easy bleeding, severe weakness.
- Severe muscle pain.
- Nausea, vomiting, pain in the upper part of the stomach, loss of appetite, dark urine, jaundice (yellowing of the skin or eyes).
- Pain in the bones (especially in the hips, legs or lower back), problems walking.
- Severe skin reaction, sore throat, fever, swelling of the tongue or face, pain in the skin, burning eyes. Also if you have a red-colored rash that spreads (especially on your upper body or face) and causes flaking and blistering.
Who should not take Epamin?
You should not use Epamin if you also take delavirdine (Rescriptor), or if you are allergic to Epamin or similar medicines such as ethotoin (Peganone), fosEpamin, etc.
To make sure Epamin is safe for you, tell your doctor if you have:
- Liver disease
- A history of suicidal thoughts or actions.
- A deficiency of vitamin D or any other condition that causes the thinning of the bones.
- Porphyria (a genetic enzyme disorder that causes symptoms that affect the skin or nervous system).
- If you drink large amounts of alcohol.
How should I take Epamin?
Follow all instructions on your prescription label. Do not take this medication in larger or smaller amounts or for longer than recommended.
Do not crush, chew, break or open an extended-release capsule. Drink it whole.
Call your doctor to get a new prescription. Shake the oral suspension (liquid) well just before taking a dose.
Measure the liquid medication with the dosing syringe provided, or with a special measuring spoon or a medicine cup. If you do not have a dose measurement device, request one from your pharmacist.
While using Epamin, you may need frequent blood tests. You may also need a blood test when you switch from one form of Epamin to another.
Visit your doctor regularly. If you are taking Epamin to treat seizures, you should not stop using Epamin suddenly, even if you feel well.
Stopping suddenly may cause increased seizures. Follow your doctor’s instructions about decreasing your dose. Tell your doctor if this medicine does not seem to work very well in treating your condition.