Compazine for Migraine Therapy

Compazine (prochlorperazine) is an prescription-strength antiemetic and antipsychotic approved for the treatment of severe nausea and vomiting, schizophrenia, and generalized non-psychotic anxiety. It is also used to relieve migraine-associated nausea and vomiting, as well as other symptoms of migraine attacks and tension headaches, particularly in the emergency setting.

Prochlorperazine is one of the first-line recommended treatments for severe migraine episodes in the emergency setting because it is effective in reducing the symptoms of migraines and headaches, comes in many formulations, and works quickly.

However, it is not used for migraine or headache prevention and is rarely given as a prescription for these conditions on a regular, long-term basis.

Prochlorperazine is recommended for medication rebound or overuse headaches, intractable headaches, status migrainosus, and for headaches and migraines in which severe nausea and vomiting are the predominant symptoms. It is also considered among the most effective medications for severe childhood migraines, with and without nausea.

The anti-headache and anti-migraine mechanisms of Compazine are not well understood, but the drug's effectiveness seems to be tied to its influence on dopamine—a neurotransmitter that acts on the brain (to modulate muscle movement, emotions, and pain) and the body (affecting gastrointestinal activity and muscle movement).

As a phenothiazine-derived antipsychotic, Compazine is a dopamine receptor antagonist, which means that it inhibits activity of this neurotransmitter. Researchers suggest that people who have migraines may be hypersensitive to dopamine and that prochlorperazine could reduce migraine and headache symptoms by modifying the neurotransmitter's effects, which have been implicated as a cause of nausea and vomiting.

The drug is believed to act both centrally (in the brain) and systemically (throughout the body, especially the digestive system).

Compazine is available in several forms. What's best for you will be determined by your doctor based on the severity of your symptoms, your ability to keep things down, and more. Options include:

• Oral (by mouth): Available in 5 mg and 10 mg tablets, sustained release 10 mg and 15 mg capsules, and as a liquid. The suggested oral dose for treatment of migraines and headaches in adults is 5 mg or 10 mg, which can be repeated every six to eight hours.
• Suppository (inserted rectally): Available in 2.5 mg, 5 mg, and 25 mg doses. The adult suppository dose is typically 25 mg for an acute migraine attack, and the maximum recommended dose is twice per day.
• Injections: Intravenous (injected into a vein, IV) and intramuscular (injected into a muscle, IM) injections can range between 2.5 mg and 10 mg, with a maximum recommended dose of 40 mg per day.

Compazine is not recommended for children younger than age 2 or who are under 20 pounds. For older children, the recommended dose for treatment of migraines and other headaches is 2.5 mg orally or rectally. IM an IV administration is not common for children, and the dose is determined on a case-by-case basis.

There are side effects associated with Compazine, but they are usually associated with chronic use. However, in some rare instances, serious adverse events can occur even after only a single dose of the medication.

Side effects can include:

• Drowsiness
• Low blood pressure
• Dizziness
• Amenorrhea (slowing or stopping of menstrual periods)
• Blurry vision
• Akathisia (physical restlessness)

Long-term use of Compazine can trigger parkinsonism, which is characterized by the same symptoms as Parkinson's disease.

It can also trigger tardive dyskinesia, which is characterized by:

• Lip smacking or puckering
• Muscle spasms of face, neck, body, arms, or legs, causing unusual body positions or unusual expressions on the face
• Rapid or worm-like movements of the tongue
• Tic-like or twitching movements

Compazine may cause neuroleptic malignant syndrome (NMS)—a potentially fatal condition characterized by muscle rigidity, an elevated body temperature, confusion, and dysregulation of the autonomic nervous system. 

Compazine can interact with other medications that make you sleepy or drowsy. Be sure to make your prescribing doctor aware of any medications, prescription or over-the-counter, and supplements that you take.

You should not use Compazine if you have an allergy or sensitivity to phenothiazines. You also should not use it if you have low blood pressure, heart problems, or motor problems such as Parkinson's disease, dystonia, or spasms.

It is not known whether Compazine will harm an unborn baby. If you have already used Compazine in the past and have the medication at home, it's important to consult your doctor before taking it if you are pregnant or if you are planning on becoming pregnant. While Compazine is sometimes used during pregnancy with caution, it is not recommended for breastfeeding mothers.

While not a typical at-home prescription therapy for headaches and migraines, Compazine is sometimes given in the emergency room. If you have severe nausea with your headaches, or if status migrainosus or medication rebound headaches are recurrent problems for you, talk to your doctor about a migraine treatment plan so that you can avoid these distressing events.