What Drugs Decrease Effectiveness Of Phenytoin?

asked in category: General Last Updated: 20th May, 2020

Drugs that may decrease phenytoin levels and reduce effectiveness include carbamazepine, chronic alcohol abuse, reserpine, and sucralfate (Carafate).

What Drugs Interact With Phenytoin?

Drugs That Affect Phenytoin Concentrations

Interacting Agent Examples Drugs that may increase phenytoin serum levels Antiepileptic drugs Ethosuximide, felbamate, oxcarbazepine, methsuximide, topiramate Azoles Fluconazole, ketoconazole, itraconazole, miconazole, voriconazole Antineoplastic agents Capecitabine, fluorouracil

What Can Cause Dilantin Levels To Drop?

Drugs which may decrease phenytoin levels include: carbamazepine, chronic alcohol abuse, reserpine. Moban brand of molindone HCl contains calcium ions which interfere with the absorption of phenytoin.

How Is Phenytoin Cleared?

Elimination occurs primarily by biotransformation to several inactive hydroxylated metabolites. Metabolites are then mostly excreted in the urine. Phenytoin follows nonlinear (or zero-order) kinetics at therapeutic concentrations, because the rate of metabolism is close to the maximum capacity of the enzymes involved.

How Does Phenytoin Work To Suppress Seizure Activity?

Phenytoin is used to control certain type of seizures, and to treat and prevent seizures that may begin during or after surgery to the brain or nervous system. Phenytoin is in a class of medications called anticonvulsants. It works by decreasing abnormal electrical activity in the brain.

What Does Phenytoin Do To The Brain?

Phenytoin is used to prevent and control seizures (also called an anticonvulsant or antiepileptic drug). It works by reducing the spread of seizure activity in the brain.

Does Phenytoin Make You Sleepy?

Phenytoin oral capsule may cause drowsiness. This can slow your thinking and motor skills. You shouldn’t drive, use machinery, or do other tasks that require alertness until you know how this drug affects you. Phenytoin can also cause other side effects.

Does Phenytoin Cause Memory Loss?

All drugs that depress signaling in the CNS can cause memory loss. Alternatives: Many patients with seizures do well on phenytoin (Dilantin), which has little if any impact on memory. Many patients with chronic nerve pain find that venlafaxine (Effexor) — which also spares memory — alleviates their pain.

Does Phenytoin Affect Blood Pressure?

Phenytoin is an effective antiepileptic drug which is used for many years in the treatment of epileptic seizures. In previous decades, several patients experienced adverse effects of intravenous phenytoin such as severe heart arrhythmias and decrease of blood pressure.

What Are The Long Term Side Effects Of Phenytoin?

Side effects of phenytoin include sedation, a cerebellar syndrome, phenytoin encephalopathy, psychosis, locomotor dysfunction, hyperkinesia, megaloblastic anemia, decreased serum folate level, decreased bone mineral content, liver disease, IgA deficiency, gingival hyperplasia, and a lupus-like hypersensitivity syndrome

What Is Phenytoin 100Mg Used For?

Phenytoin is an anti-epileptic drug, also called an anticonvulsant. Phenytoin works by slowing down impulses in the brain that cause seizures. Phenytoin is used to control seizures. It does not treat all types of seizures, and your doctor will determine if it is the right medicine for you.

Can Phenytoin Cause Liver Damage?

Phenytoin is an anticonvulsant that in rare cases can cause acute idiosyncratic drug-induced liver disease that can be severe or even fatal. The liver injury caused by phenytoin appears to be due to a hypersensitivity reaction and resembles cases of immunoallergic hepatotoxicity.

What Is A Normal Phenytoin Level?

Although the reference range is between 10 and 20 µg/mL, about half of patients’ seizures are controlled at values lower and higher than the therapeutic range. Some adverse effects of phenytoin are related to specific serum levels. Nystagmus is frequently observed at levels greater than 20 µg/mL.

How Is Phenytoin Absorbed?

The absorption of phenytoin was studied in man. It is concluded that phenytoin absorbed from the intestine is recirculated via the bile, so that blood levels do not accurately reflect absorption. Phenytoin is loosely bound to serum proteins and is found in red cells in concentrations similar to those in plasma.

How Do You Prepare Phenytoin Infusion?

For administration by intravenous infusion phenytoin injection should be diluted in 50 – 100 ml of normal saline, and the final concentration of phenytoin in the solution should not exceed 10 mg/ml, the infusion mixture should not be refrigerated.

What Is The Half Life Of Phenytoin?

The plasma half-life in man after oral administration of phenytoin averages 22 hours, with a range of 7 to 42 hours. Steady-state therapeutic levels are achieved at least 7 to 10 days (5–7 half- lives) after initiation of therapy with recommended doses of 300 mg/day.

What Happens If Phenytoin Is Low?

Phenytoin blood testing is ordered because phenytoin blood levels must be maintained within a narrow therapeutic range. If levels are too low, the affected person may experience seizures; if they are too high, the person may experience symptoms associated with phenytoin toxicity.

Can Phenytoin Get You High?

Like many prescription drugs, Dilantin abuse can occur for both patients and non-patients. In most cases of abuse, the user is trying to achieve a Dilantin high. Although Dilantin is not a major drug of abuse, Dilantin toxicity can occur and can lead to death.

Which Drug Is Considered First Line Treatment For Partial And Tonic Clonic Seizures?

For generalised tonic-clonic seizures, sodium valproate is recommended as first-line treatment. If this is unsuitable, lamotrigine is recommended. Carbamazepine and oxcarbazepine can be considered as alternatives.