Headaches are a common ailment that can last anywhere from a few minutes to days or even weeks. The type, intensity and duration of headaches vary greatly depending on factors such as the person's age, health history, and underlying cause. Generally speaking, tension headaches tend to be most mild and often resolve within an hour or two with simple over-the-counter pain relievers like ibuprofen or acetaminophen. Migraine headaches usually last for several hours between four to 72 hours and can range from moderate to severe in intensity. Cluster headaches come in short bursts lasting 15 minutes up to three hours at a time but may recur throughout the day and night for several weeks before dissipating completely. Other types of headache, such as those caused by sinus infections or some medical conditions, may also have varying lengths with no clear pattern of resolution. In all cases however it is important to seek help if your headache does not improve after taking medication as this could indicate more serious underlying causes requiring attention by your doctor.