Prescription Preventive Medications for Migraine
Roger K. Cady, MD
Preventive medications are designed to protect the nervous system from attacks of migraine. They are prescribed to change the pattern and frequency of migraine attacks. It is important to realize that preventive medications make the nervous system more resistant to migraine but rarely are they able to prevent all future migraine attacks. Preventive migraine medications should be considered an important factor that raises the migraine threshold by protecting the hyperexcitablenervous systemnature provided for people with migraine.
Preventive medications may provide other benefits. Sometimes they may help an acute medication work better. Also they can help stabilize the nervous system between migraine attacks and help control other diseases and medical conditions that frequently occur in people with migraine. For example, if a person has high blood pressure, depression, or anxiety as well as migraine, certain migraine medications can be used to help both conditions.
Preventive medications should be considered for migraineurs in the following circumstances:
- Migraine is frequent (3 or 4 days per month).
- Migraine significantly interferes with the patient’s daily routine despite acute treatment. In other words, migraine may be infrequent (perhaps2 days per month) but adequate treatment provided by acute treatment is not sufficient to reduce the disability of the attack in a timely manner.
- Failure, contraindication to, or troublesome side-effects from acute medications.
- Overuse of acute medications;
- The frequency of attacks is increasing over time
- Patient preference, that is, the desire to have as few acute attacks as possible.
It is not clear how preventive therapy works, although it seem likely that it modifies the sensitivity of the brain that underlies migraine. In addition, for a person with a concomitant illness that requires daily treatment, the clinician can prescribe a drug that treats both migraine and the concomitant illness.
Preventive medications for migraine are grossly under-utilized. In fact, it is estimated that only about 13% of those in need of preventive medication actually use it. Far fewer of those who have it prescribed are using it properly. The following answers to frequently asked questions can assist in understanding the basics of preventive medication for migraine.
1.) Why do I take a medication every day when migraine occurs only several times a month? Patients with migraine are born with a unique nervous system. This nervous system is still vulnerable to migraine even when you do not have a headache At times in your life when migraines are more frequent, you are more susceptible to migraine attacks.
2.) Can preventive medications eventually be stopped? Yes, especially if you have had frequent migraines for only a short period of time or there are specific events putting you at risk for migraine that are expected to resolve over time (for example, a divorce or death of a parent) or when depression or anxiety complicates the occurrence of attacks. However when migraine frequency increases, there is a danger of transformation from an episodic event toa chronic condition (15 or more headache days per month). Preventive medication is prescribed to stop this transformation before migraine becomes chronic.
3.) What about side effects? The nervous system of a migraine sufferer is very often more sensitive to the effects of medication. This can be overcome by following the old adage of “start low and go slow.” This means that preventive medication needs to be started at a low dosage and then increased slowly over time to allow the body to adjust to the medication and detect side effects if they emerge. Dosages then can be individualized to provide the best balance between effectiveness and side effects. If that cannot be achieved, then a different medication is required.
4.) Are there things I should do to make my preventive medications work better? Yes, preventive medications are not the total answer. Adding activities that nurture your nervous system such as daily exercise, yoga, massage, biofeedback, or humor all add immeasurable benefit to your medication.
5.) How do preventive medications work? There are several different types of preventive medications and each works in a unique fashion. The most common fall into 3 classes: beta blockers, tricyclic antidepressants, and neuronal stabilizers.
Beta blockers block adrenaline-like chemicals that are releasedwhen a body is under stress. The adrenaline- like chemicals excite the nervous system which can make somepeople prone to attacks of migraine. Also the “let down” after stress puts others at risk for migraine. Beta blockers may also help migraine by interacting with serotonin receptors in the brain that help protect against migraine. Beta blockers are generally useful if stressful events or the let down from stressful events cause migraine or if there is a tendency for panic attacks or high blood pressure.
Tricyclic antidepressants work by preventing the serotonin released by nerve cells from being metabolized or broken down by the body as rapidly as it would normally be. This means there is more serotonin available for nerve cells to communicate with each other. Serotonin may be considered a “brake pedal” for the nervous system and in this way, prevents migraine. Serotonin helps regulate sleep, mood, and pain. Tricyclic antidepressants are often used to prevent migraine when there is sleep disturbance or mood disruption associated with migraine. These medications are generally used at much lower doses than those used to treat depression.
Neuronal stabilizers are medications that stabilize hyperactive nerve circuits in the brain. At higher doses these medications are used to treat seizures. These medications protect the migraine threshold from being so easily activated.
Putting it Altogether
Medications are an important aspect of migraine care. They are a tool you need to understand and participate in managing. This begins with having a clear understanding of the target of the medication, goals to measure its usefulness, and a method for monitoring its effects over time. Keeping a headache diary/calendar provides a template for future decisions and can assist in confident decision making.
Table 1:Preventive Therapies for Migraine
|Generic Treatment Doses|
|Divalproex sodium tablets*||500 mg to 1500 mg/day|
|Topiramate tablets*||50 mg to 400 mg|
|Zonisamide capsules||100 mg to 400 mg|
|Tricyclic AntidepressantsAmitriptyline tablets*Nortriptyline tablets||30 mg to 150 mg30 mg to 100 mg|
|Atenolol tablets*Metoprolol tabletsNadolol tabletsPropranolol tablets*Timolol tablets||25 mg to 100 mg50 mg to 200 mg20 mg to 200 mg30 mg to 240 mg10 mg to 30 mg|
|Botulinum toxin A injection||155 units in 31 injection sites|
|Gelstat sublingual homeopathic gel||2 2ml|
|Magnesium gluconate tablets||400 mg to 600 mg/day|
|Riboflavin tablets (Vitamin B2)||400 mg/day|
|Petasites 75 mg||75 mg bid|
* Approved by the FDA.