Headaches or facial pressure associated with sinusitis are often accompanied by some degree of nasal congestion or blockage. If you can relieve sinus pressure by spraying your nose with an over-the-counter decongestant spray (Neo-Synephrine, Afrin) or by taking a decongestant tablet (Sudafed), that suggests that the pressure or headache is sinus in origin. If your headache is stress related, or if it is a migraine, then the decongestants (spray or tablets) will have little effect. Remember that the use of nonprescription decongestant sprays should be limited to three to five days only. Decongestant tablets should not be taken with any regularity by people with high blood pressure or men with prostate problems.