Mirtazapine Relieves Postdural Puncture Headache

Abstract

To the Editor: According to the Monro-Kellie doctrine,1 cerebral vasodilatation is one of the possibilities of postdural puncture headache (PDPH). It follows, therefore, that a vasoconstrictor might relieve PDPH, by a means other than replacing lost CSF volume or sealing the dural rent.2 We report here an example of a patient whose PDPH resolved following mirtazapine, a drug used as a prophylactic treatment for migraine headache. A 55-yr-old woman sustained inadvertent dural puncture during epidural anesthesia with an 18-gauge Tuohy needle using loss of resistance to air technique. Twenty-eight hours later, she developed a severe headache over the occipitoparietal area with radiation to the neck. The headache occurred within 10 min after arising and was relieved within 15 min in the recumbent position. She had no history of migraine or other types of headache. Nausea and vomiting but no visual or hearing disturbances were noted. She refused an epidural blood patch. Because of its potential cerebral vasoconstrictive effect and possible antinociceptive activity,3,4 mirtazapine 30 mg PO was given at bedtime with resolution of the headache the next morning. Treatment was continued for the ensuing 3 days with sustained pain relief. Activation of 5-HT1 receptors (notably 5-HT1B/1D) by mirtazapine could possibly treat PDPH by constriction of dilated cerebral vessels.5,6 In addition, mirtazapine might act as a 5-HT2/3 receptor antagonist, and it can potentiate endogenous opioid systems.7 The peak plasma concentration of mirtazapine is reached 2 h after single dose and the elimination half-life ranges from 20 to 40 h, making the drug suitable for once daily administration.8 Although mirtazapine may represent an option in patients who refuse an epidural blood patch, it may not be suitable in nursing mothers because the drug falls in the category of “effect on nursing infants is unknown, but may be of concern.” Michael J. Sheen, MD Shung-Tai Ho, MD, MS Department of Anesthesiology Tri-Service General Hospital National Defense Medical Center Taipei, Taiwan [email protected]