Anticonvulsants

What are Anticonvulsants?

Anticonvulsants (antiepileptics or AEDs) helps to normalise the way nerve impulses travel along the nerve cells which helps prevent or treat seizures. When the brain is working normally the nerve cells talk to each other using controlled electrical signals from one nerve cell to another. This tells the body to do everything it needs or wants to do. During a seizure there is a change in the level of nerve cell electrical signals from a normal level to an excessive or abnormal amount of nerve signals. This increased nerve activity is responsible for the signs and symptoms of a seizure. What causes the change is nerve impulses can be the result of an injury to part of the brain, stroke, brain tumor, genetic causes, metabolic problems or toxicity issues. Anticonvulsants can also be used to treat nerve pain and bipolar disorder.

How they work?

Anticonvulsants keep the nerve cell impulses to a normal level so they don’t become excessive and uncontrolled, which is why they are used in seizure disorders and epilepsy. The way anticonvulsants control the nerve impulses is not fully understood but is thought to be by their action on neurotransmitters like GABA, or acting on receptors such as glutamate or by changing the electrical channels in the nerve cell.

What they treat

Anticonvulsants stabilize the level of nerve cell impulses and are used for a range of conditions including epilepsy, seizure disorders, nerve pain (neuropathic pain) and bipolar disorder.

Benzodiazepine anticonvulsants

Benzodiazepines enhance activation of GABA receptors and act as central nervous system depressants. They inhibit spread of discharge that causes seizures in epileptics.

Benzodiazepines are effective anticonvulsants but due to their sedative effect they are rarely used as maintenance therapy. Diazepam, a benzodiazepine, is given intravenously to treat status epilepticus, which can be a life threatening condition where seizures occur almost continuously.

Diazepam 

                  is a benzodiazepine. It affects chemicals in the brain that may be unbalanced in people                  with anxiety.

Diazepam is used to treat anxiety disorders, alcohol withdrawal symptoms, or muscle spasms. Diazepam is sometimes used with other medications to treat seizures.

Diazepam may also be used for purposes not listed in this medication guide.

  You should not use this medicine if you are allergic to diazepam or similar medicines (Ativan, Klonopin, Restoril, Xanax, and others), or if you have myasthenia gravis, severe liver disease, narrow-angle glaucoma, a severe breathing problem, or sleep apnea.

   Before you take diazepam, tell your doctor if you have glaucoma, asthma or other breathing problems, kidney or liver disease, seizures, or a history of drug or alcohol addiction, mental illness, depression, or suicidal thoughts.

  Do not start or stop taking diazepam during pregnancy without your doctor's advice. Diazepam may cause harm to an unborn baby, but having a seizure during pregnancy could harm both the mother and the baby. Tell your doctor right away if you become pregnant while taking diazepam for seizures.
Diazepam may be habit-forming. Misuse of habit-forming medicine can cause addiction, overdose, or death.Do not give this medication to a child younger than 6 months old

            Usual Adult Dose for Anxiety

ORAL:2 to 10 mg orally 2 to 4 times a day
PARENTERAL:Moderate Anxiety Disorders and Symptoms: 2 to 5 mg IM or IV, repeated in 3 to 4 hours if necessarySevere Anxiety Disorders and Symptoms: 5 to 10 mg IM or IV, repeated in 3 to 4 hours if necessary
Comments:-Oral doses should be determined by the severity of symptoms.-Anxiety associated with the stress of everyday life usually does not require treatment with this drug.
Use: Management of anxiety disorders and short-term relief of anxiety symptoms

                     Usual Adult Dose for Alcohol Withdrawal

ORAL:-Initial dose: 10 mg orally 3 to 4 times a day for the first 24 hours-Maintenance dose: 5 mg orally 3 to 4 times a day as needed
PARENTERAL:10 mg IM or IV once, then 5 to 10 mg IM or IV in 3 to 4 hours if necessary
Use: Symptomatic relief of acute agitation, tremor, impending/acute delirium tremens, and hallucinations in acute alcohol withdrawal             

            Usual Adult Dose for Muscle Spasm

ORAL:2 to 10 mg orally 3 to 4 times a day
PARENTERAL:5 to 10 mg IM or IV, then 5 to 10 mg IM or IV in 3 to 4 hours if necessary
Comment:-Larger parenteral doses may be necessary for patients with tetanus.
Use: Adjunctive treatment for the relief of skeletal muscle spasm due to reflex spasm to local pathology, spasticity caused by upper motor neuron disorders, athetosis, and stiff-man syndrome (e.g., inflammation of the muscles/joints secondary to trauma, cerebral palsy, paraplegia)

                      Usual Adult Dose for Seizures

ORAL:2 to 10 mg orally 2 to 4 times a day
RECTAL:-Initial dose: 0.2 mg/kg rectally, rounded upward to the next available dose. A 2.5 mg rectal dose may be given as a partial replacement if patients expel a portion of the initial dose-If necessary, a second dose of 0.2 mg/kg may be given rectally 4 to 12 hours after the first dose.-Maximum Frequency: May be used to treat up to 1 seizure episode every 5 days, and no more than 5 episodes/month
Uses:-Management of selected, refractory patients with epilepsy on stable regimens of antiepileptic drugs who require intermittent use of this drug to control bouts of increased seizure activity-Adjunctive treatment for convulsive disorders.

 Clonazepam 

is a benzodiazepine. It affects chemicals in the brain that may be unbalanced. Clonazepam is also a seizure medicine, also called an anti-epileptic drug.Clonazepam is used to treat certain seizure disorders (including absence seizures or Lennox-Gastaut syndrome) in adults and children.Clonazepam is also used to treat panic disorder (including agoraphobia) in adults.

 You should not use clonazepam if you have narrow-angle glaucoma or severe liver disease, or if you are allergic to Valium or a similar medicine.

Do not drink alcohol while taking this medicine. Clonazepam may be habit-forming. Never share clonazepam with another person. Keep the medication in a place where others cannot get to it. Selling or giving away clonazepam is against the law.

           Usual Adult Dose for Seizure Prophylaxis

1.5 mg orally per day divided into 3 doses; this may be increased in increments of 0.5 mg to 1 mg every 3 days until seizures are adequately controlled or until side effects preclude any further increase.
Maximum dose: 20 mg orally per day
Comments:
-The use of multiple anticonvulsants may result in an increase of depressant adverse effects.
Use:
-Alone or as an adjunct in the treatment of the Lennox-Gastaut syndrome (petit mal variant), akinetic and myoclonic seizures

                     Usual Adult Dose for Panic Disorder

Initial dose: 0.25 mg orally 2 times per day
Maintenance dose: 1 mg orally per day
Maximum dose: 4 mg orally per day

Comments:
-An increase to the target dose for most patients of 1 mg/day may be made after 3 days.
-The dose may be increased in increments of 0.125 mg to 0.25 mg 2 times per day every 3 days until panic disorder is controlled or until side effects make further increases undesired.
-Administration of one dose at bedtime may be desired, to reduce the inconvenience of somnolence.
-Treatment should be discontinued gradually, with a decrease of 0.125 mg 2 times per day every 3 days, until the drug is completely withdrawn.

Lorazepam 

        belongs to a group of drugs called benzodiazepines. It affects chemicals in the brain that may be unbalanced in people with anxiety.
Lorazepam is used to treat anxiety disorders.

You should not use lorazepam if you have narrow-angle glaucoma or myasthenia gravis, or if you are allergic to Valium or a similar medicine.
Do not drink alcohol while taking lorazepam. This medication can increase the effects of alcohol.

Do not use lorazepam if you are pregnant. This medicine can cause birth defects or life-threatening withdrawal symptoms in a newborn.

 Lorazepam may be habit-forming and should be used only by the person it was prescribed for. Misuse of habit-forming medicine can cause addiction, overdose, or death.Lorazepam should never be shared with another person, especially someone who has a history of drug abuse or addiction. Keep the medication in a secure place where others cannot get to it.

                                  Usual Adult Dose for Anxiety

Tablets:
Initial dose: 2 to 3 mg orally per day administered 2 to 3 times per day
Maintenance dose: 1 to 2 mg orally 2 to 3 times a day
Parenteral:
IV: 2 mg total, or 0.044 mg/kg, whichever is smaller
Comments:
-The daily dosage may vary from 1 to 10 mg per day.
-The dosage should be increased gradually when needed to help avoid adverse effects.
-When higher dosage is indicated, the evening dose should be increased before the daytime doses.
Use: Management of anxiety disorders or for the short-term relief of the symptoms of anxiety or anxiety associated with depressive symptoms

                                   Usual Adult Dose for Light Anesthesia

IM: 0.05 mg/kg up to a maximum of 4 mg
IV: 2 mg total, or 0.044 mg/kg, whichever is smaller
Comments:
-Doses of other injectable central-nervous-system depressant drugs should be reduced.
-For optimum effect, intramuscular drug should be administered at least 2 hours before the anticipated operative procedure.
-Narcotic analgesics should be administered at their usual preoperative time.
-IV: This dose should not ordinarily be exceeded in patients over 50 years of age.
-IV: Larger doses as high as 0.05 mg/kg up to a total of 4 mg may be administered.
-For optimum effect, intravenous drug should be administered 15 to 20 minutes before the anticipated operative procedure.
Use:
-Preanesthetic medication for adult patients, producing sedation (sleepiness or drowsiness), relief of anxiety, and a decreased ability to recall events related to the day of surgery

                                    Usual Adult Dose for Status Epilepticus

0.1 mg/kg IV up to 4 mg per dose; may repeat in 5 to 10 minutes
Maximum dose: 8 mg
Comments:
-Vital signs should be monitored, an unobstructed airway should be maintained, and artificial ventilation equipment should be available.
-When an intravenous port is not available, the IM route may prove useful.
Use: Treatment of status epilepticus

                                      Usual Adult Dose for Insomnia

2 to 4 mg orally administered at bedtime
Comments:
-The dosage should be increased gradually when needed to help avoid adverse effects.
Use: Management of insomnia
Usual Geriatric Dose for Anxiety
Elderly or debilitated patients:
1 to 2 mg orally per day in divided doses

Barbiturate anticonvulsants

Barbiturate anticonvulsants are a group of drugs derived from barbituric acid and they act by suppressing activity of the central nervous system. Barbiturate anticonvulsants enhance the action of GABA, which is an inhibitory neurotransmitter, and inhibits initiation of discharge that would start the seizure. Barbiturates facilitate GABA-mediated opening of chloride channels and increases effectiveness of GABA.

Barbiturates are used to treat all types of seizures except absence seizures.

Phenobarbital Elixir

Uses of Phenobarbital Elixir:

• It is used to help control certain kinds of seizures.
• It is used to treat sleep problems.
• It may be given to you for other reasons. Talk with the doctor.

 How is this medicine (Phenobarbital Elixir) best taken?

Use this medicine as ordered by your doctor. Read all information given to you. Follow all instructions closely.

• Take with or without food. Take with food if it causes an upset stomach.
• Measure liquid doses carefully. Use the measuring device that comes with phenobarbital elixir. If there is none, ask the pharmacist for a device to measure this medicine.

Usual Adult Dose for Sedation

Daytime Sedation:
30 to 120 mg orally, IM, or IV in 2 or 3 divided doses
Maximum dose: 400 mg during a 24-hour period

Preoperative Sedation:
Parenteral:
100 to 200 mg IM 60 to 90 minutes before surgery

Comments:
-Frequency of administration should be determined by the patient response.
-Parenteral administration should be reserved for situations in which oral administration is impossible/impractical.

Uses: Daytime sedation; preoperative sedation

Usual Adult Dose for Insomnia

Oral:
-Recommended dose: 100 to 200 mg orally once a day
-Maximum dose: 400 mg during a 24-hour period

Parenteral:
-Recommended dose: 100 to 320 mg IM or IV once a day
-Maximum dose: 400 mg during a 24-hour period

Comments:
-This drug may begin to lose effectiveness for inducing and maintaining sleep after 2 weeks.

Uses: Bedtime hypnosis; hypnosis

Usual Adult Dose for Seizures

Acute Convulsions
Parenteral:
20 to 320 mg IM or IV every 6 hours as necessary

Anticonvulsant:
Oral:
60 to 200 mg orally per day

Comments:
-Maintenance doses should be determined by clinical laboratory reference values.
-Prevention of febrile seizures may not influence the development of epilepsy.

Uses: Treatment of generalized and partial seizures; treatment/prophylaxis of febrile seizures

Usual Pediatric Dose for Seizures

Anticonvulsant:
Oral:
-Initial dose: 15 to 20 mg/kg orally
-Recommended dose: 3 to 6 mg/kg orally

Parenteral:
4 to 6 mg/kg/day for 7 to 10 days or 5 to 15 mg/kg/day IM or IV

Status epilepticus:
Parenteral:
-Initial dose: 15 to 20 mg/kg IV over 10 to 15 minutes

Comments:
-Loading doses of 15 to 20 mg/kg are predicted to produce blood levels of approximately 20 mcg/mL after administration.
-Maintenance doses should be determined by clinical laboratory reference values.
-Prevention of febrile seizures may not influence the development of epilepsy.