haloperidol

Haldol (haloperidol) is an antipsychotic medication used to treat schizophrenia and acute psychosis. It is also used to control tics and vocal utterances that are part of Tourette's syndrome.

The most common side effects of haloperidol are:

• extrapyramidal effects (sudden, often jerky, involuntary motions of the head, neck, arms, body, or eyes, muscle stiffness, akathisia, Parkinsonism),
• dizziness,
• hyperactivity,
• tiredness, and
• nausea.

Other important side effects of haloperidol are:

• sedation,
• weight gain,
• erectile dysfunction,
• menstrual irregularities,
• insomnia,
• gynecomastia,
• dry mouth, 
• vomiting, and
• constipation

Haloperidol may cause a condition called "orthostatic hypotension" during the early phase of treatment (first week or two). Orthostatic hypotension causes patients to become dizzy upon arising from a lying or sitting position because of a drop in blood pressure.

Haloperidol also may cause abnormal heart beats, sudden death, seizures, decreases in red and white blood cells, and withdrawal symptoms.

Elderly patients with dementia-related psychosis and treated with antipsychotic drugs such as haloperidol are at an increased risk of death.

• The recommended oral dose for schizophrenia is 0.5-5 mg two or three times daily up to a maximum dose of 30 mg daily.
• The lactate solution dose is 2-5 mg every 4-8 hours as needed by intramuscular injection.
• The lactate solution may also be administered by intravenous injection at 1-2 mg every 2-4 hours and titrated to effect.
• The maximum single injection dose is 50 mg and the maximum daily dose is 500 mg daily.
• The dose for the decanoate solution is 10-20 times the daily oral dose once monthly by intramuscular injection. The decanoate solution should not be administered intravenously.
• The recommended dose for treating Tourette's syndrome is 0.5-5 mg orally two or three times daily.

Haloperidol causes sedation, and sedation may be greater if haloperidol is taken with alcohol and other drugs that can cause sedation such as the benzodiazepine class of anti-anxiety drugs for example:

• diazepam (Valium)
• lorazepam (Ativan)
• clonazepam (Klonopin)
• alprazolam (Xanax)

The narcotic class of pain medications and its derivatives for example:

• oxycodone and acetaminophen (Percocet)
• hydrocodone/acetaminophen (Vicodin)
• Dilaudid
• Codeine,
• propoxyphene (Darvon)

The tricyclic class of antidepressants for example:

• amitriptyline (Elavil, Endep)
• imipramine (Tofranil)
• desipramine (Norpramin)

Some antihistamines for example:

• hydroxyzine (Atarax, Vistaril)
• diphenhydramine (Benadryl)
• Tavist

Certain antihypertensive medications for example:

• clonidine (Catapres)
• propranolol (Inderal)

Carbamazepine (Tegretol) may increase the elimination of Haldol, rendering the haloperidol less effective. Rifampin (Rifadin) may decrease the elimination of haloperidol, increasing the risk of side effects from haloperidol.

• Neonates exposed to antipsychotics during the 3rd trimester of pregnancy may develop withdrawal symptoms and extrapyramidal symptoms.
• Haloperidol is secreted into breast milk. It should not be used while breastfeeding.

Do I need a prescription for haloperidol?

• Yes.

What preparations of haloperidol are available?

• Tablets: 0.5, 1, 2, 5, 10, and 20 mg.
• Oral Concentrate: 1 and 2 mg/ml.
• Injectable solution (lactate): 5 mg/ml;
• Injectable solution (decanoate): 50 and 100 mg/ml.

How should I keep haloperidol stored?

• Tablets should be stored at room temperature, 15-30 C (59-86 F).

How does haloperidol work?

• Haloperidol interferes with the effects of neurotransmitters in the brain which are the chemical messengers that nerves manufacture and release to communicate with one another. Haloperidol blocks receptors for the neurotransmitters (specifically the dopamine and serotonin type 2 receptors) on the nerves. As a result, the nerves are not "activated" by the neurotransmitters released by other nerves.

When was haloperidol approved by the FDA?

• Haloperidol was approved by the FDA in 1967.