Can Folic Acid Cause a Headache?

Folic acid plays crucial roles in metabolism and other body processes. You need folic acid daily for proper function, and you can consume folic acid-rich foods such as oranges, spinach and lentils. If you are at risk for a deficiency, your doctor may recommend daily supplements. Folic acid does not typically result in side effects such as headaches, but knowing possible side effects and headache causes may help you determine the source of your headache 2.

Is This an Emergency?

If you are experiencing serious medical symptoms, seek emergency treatment immediately.


A headache may occur in various locations and as various types of pain, such as a dull or sharp pain or a pain that seems to radiate to multiple locations in your head. Migraine sufferers may experience intense pain that limits their physical activity and may cause light and sound sensitivities.

Food sources of folic acid and supplements do not have a connection to headaches. As well, a deficiency in folic acid and high levels of intake are not known causes of headaches. If you experience frequent headaches, keep track of what you eat, physical activity and emotional state prior to the onset of a headache. Also note any medications and supplements you take. If you notice a pattern, this could help you identify the cause of your headaches.

Other Causes

Although folic acid does not have a known connection to headaches, your headaches may occur for a variety of reasons. Tension, stress, high blood pressure and sinus infections may cause headaches. Teeth and ear conditions may also contribute to headaches. Other more serious conditions such as strokes and tumors could also cause headaches.

Possible Side Effects

If you take folic acid supplements you will most likely not experience side effects 2. However, in rare cases, you could have an allergic reaction to the supplement. Your symptoms may include rash or swelling of your lips, mouth, tongue and other facial areas. You may experience difficulty breathing as well. If your doctor gives you an injection of folic acid, you may have localized symptoms around the infection site. These side effects include redness, swelling and pain.


If you have frequent or recurrent headaches, contact your doctor. She will want to know if you have noticed any trigger patterns in your headaches. If your doctor cannot find a cause for your headaches on examination, she may order tests that may include blood work, CT scans or MRIs, which will allow her to determine if you have a health condition causing your headaches.