Preventive medications can reduce the frequency, severity and length of migraines and may increase the effectiveness of symptom-relieving medicines used during migraine attacks. Your doctor may recommend that you take preventive medications daily, or only when a predictable trigger, such as menstruation, is approaching.

In most cases, preventive medications don't eliminate headaches completely, and some cause serious side effects. If you have had good results from preventative medicine and have been migraine-free for six months to a year, your doctor may recommend tapering off the medication to see if your migraines return without it.

For best results, take these medications as your doctor recommends:

• Cardiovascular drugs. Beta blockers — commonly used to treat high blood pressure and coronary artery disease — can reduce the frequency and severity of migraines. These drugs are considered among first-line treatment agents. Calcium channel blockers, another class of cardiovascular drugs, especially verapamil (Calan, Isoptin), also may be helpful in preventing migraines and relieving symptoms from aura. In addition, the antihypertensive medications lisinopril (Prinivil, Zestril) and candesartan (Atacand) are useful in reducing the length and severity of migraines. Researchers don't understand exactly why all of these cardiovascular drugs prevent migraines. Side effects can include dizziness, drowsiness or lightheadedness.
• Antidepressants. Certain antidepressants are good at helping to prevent some types of headaches, including migraines. Most effective are tricyclic antidepressants, such as amitriptyline, nortriptyline (Pamelor) and protriptyline (Vivactil). These medications are considered among first-line treatment agents and may reduce migraines by affecting the level of serotonin and other brain chemicals. You don't have to have depression to benefit from these drugs. Other classes of antidepressants called selective serotonin reuptake inhibitors (SSRIs) and serotonin and norepinephrine reuptake inhibitors (SNRIs), haven't been proven as effective for migraine prevention. However, preliminary research suggests that one SNRI, venlafaxine (Effexor), may be helpful in preventing migraines.
• Anti-seizure drugs. Some anti-seizure drugs, such as divalproex (Depakote) and topiramate (Topamax), and gabapentin (Neurontin), seem to reduce the frequency of migraines. In high doses, however, these anti-seizure drugs may cause side effects, such as nausea and vomiting, diarrhea, cramps, hair loss, and dizziness.
• Cyproheptadine. This antihistamine specifically affects serotonin activity. Doctors sometimes give it to children as a preventive measure.
• Botulinum toxin type A (Botox). Botulinum toxin type A is sometimes used for treatment of chronic migraines. Studies have had mixed results with respect to effectiveness. However, some headache specialists believe that it can be helpful for some people. Injections are made in muscles of the forehead and neck. When this is effective, the treatment typically needs to be repeated every three months.

Preventive, or “prophylactic,” medicines are taken every day to prevent headaches from starting. They are used to treat chronic headaches that occur more than twice a week and/or are extremely painful. They are also prescribed when other headache medicines or remedies do not work or cannot be used. More commonly-used medicines include:

• Tricyclic anti-depressants (TCAs) – These medicines were originally used to treat depression and related disorders. However, headache experts have learned that TCAs can also help prevent and relieve chronic TTH. A TCA such as amitriptyline (Elavil) is often the first medicine of choice for preventing chronic TTH. TCAs are often begun at lower doses and are slowly increased. In addition to relieving pain, TCAs may improve sleep and decrease depression in people who have it. Other TCAs given for chronic TTH include nortriptyline (Pamelor), desipramine (Norpramin), doxepin (Sinequan) and clomipramine (Anafranil).

• Anti-convulsants – These medicines were originally used to treat seizures (convulsions or epilepsy). Now, certain anti-convulsants are also used to help prevent chronic TTH. Your health care provider may give you an anti-convulsant if TCAs failed to relieve your headaches. Examples include valproic acid (Depakote), gabapentin (Neurontin) and topiramate (Topamax).

Other Medicines

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  Muscle relaxants – These medicines are also called “anti-spasmodics.” They given to relax tight muscles. They may be given alone, but medical research shows that they are more effective when given together with a medicine such as a TCA. Examples of muscle relaxants are tizanidine (Zanaflex) and metaxalone (Skelaxin). More research needs to be done on the effectiveness of muscle relaxants as a treatment for TTH.