What Is Dilantin, and How Is It Used and Abused?

Dilantin(phenytoin) is one of the first anticonvulsant medications1 as it was developed in the early 1900s. Its major uses are for the prevention of seizures, particularly tonic-clonic seizures (that affect the entire brain) or partial seizures (seizures that affect only half of the brain or one area).  Phenytoin can also be used in the treatment of arrhythmia (irregular heartbeat) and neuropathic pain.  

The drug can be taken orally or administered intravenously. The intravenous form is typically used for seizures that last longer than five minutes, or for the occurrence of two or more seizures that occur within a five-minute period of time; both of these conditions are often referred to as status epilepticus.

In some cases, anticonvulsant medications like Dilantin may also be used in the treatment of mood disorders, such as for certain forms of bipolar disorder. Dilantin is not approved for this use, but there are some reports of off-label use for this purpose.  

Dilantin is one of the most widely prescribed drugs in the world. It is now often used as a second-line approach to seizures, but it still remains very crucial in the treatment of status epilepticus, seizures that occur following surgery, or seizures that occur in a hospital.

Dilantin Side Effects

Powerful a woman holding a handful of Vicodin drugs like Dilantin produce significant changes in a person’s body chemistry. There is no such thing as a drug that does not have some side effects associated with its use. Dilantin is no exception. Some of the potential side effects include:

  • Issues with the gums similar to gingivitis
  • Nausea, stomach cramps, and/or loss of appetite
  • Dizziness, decreased coordination, and mild problems with attention
  • Increased growth of hair

Some of the more serious effects associated with Dilantin include:

  • Insomnia
  • Potential suicidality in some individuals
  • Liver damage
  • Hypotension
  • Bone marrow problems
  • Weakening of the bones and the development of osteoporosis (Patients maintained on Dilantin for extended periods of time are encouraged to take supplements.)
  • Neuropathy, or tingling and pain or numbness in the feet and legs particularly
  • The potential for birth defects if taken during pregnancy
  • The development of mild tremors
  • In very rare cases, atrophy of the cerebellum in the brain

A small number of individuals may develop an allergic reaction to Dilantin, and these individuals should contact their physician immediately.

It is not recommended that individuals who use the drug for seizure control stop taking the drug unless they are instructed to do so by their physician due to the potential for the reoccurrence of seizures that may be very severe.

Abuse Potential of Dilantin

There are a few scattered case accounts of abuse of anticonvulsant medications, particularly occurring in the context of other substance abuse, such as alcohol abuse. Often, when anticonvulsant drugs are misused by individuals with seizure disorders who have a prescription for them, these individuals also have coexisting cognitive disorders or psychiatric/psychological disorders.

The use of alcohol in conjunction with Dilantin will reduce the effectiveness of the medication and may cause idiosyncratic side effects, but most likely, it will not result in any additional significant psychoactive effects.

Dilantin is not a major drug of abuse; its use does not produce significant euphoria even though it may be used to control certain types of pain; and the drug is not considered to be a controlled substance by the United States Drug Enforcement Administration2, although its use does require a prescription. Powerful drugs like Dilantin should only be used under the supervision of a physician due to their mechanism of action and potential side effect profile.

If you or your loved one is concerned about overuse or abuse of Dilantin, we are available to help 24/7 at .

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