An official website of the United States government
The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before
sharing sensitive information, make sure you’re on a federal
government site.
The site is secure.
The https:// ensures that you are connecting to the
official website and that any information you provide is encrypted
and transmitted securely.
Gilman-Sachs A, Robbins L, Baum L.Gilman-Sachs A, et al.Headache. 1989 May;29(5):290-4. doi: 10.1111/j.1526-4610.1989.hed2905290.x.Headache. 1989.PMID: 2787308