AMS headache is usually intense, throbbing and is either generalized or in the forehead. It develops within six hours to four days of arrival at high altitude and can last for up to five days. The headache often worsens with exertion, coughing, straining or lying flat.

An altitude headache, the most common symptom of Acute Mountain Sickness (AMS), typically lasts between 24 to 48 hours as your body undergoes the process of acclimatization. These headaches generally occur within 6 to 12 hours of ascending to altitudes above 8,000 feet (2,400 meters). If you remain at the same altitude and allow your body to rest, the symptoms usually subside on their own as your breathing rate adjusts to the lower oxygen levels. However, if the headache is accompanied by severe nausea or confusion, it is a sign that you must descend immediately. In 2026, health experts recommend staying hydrated and avoiding alcohol to help the symptoms clear faster. Over-the-counter pain relievers like ibuprofen or acetaminophen are effective for managing the pain, but the only "true" cure for a persistent altitude headache that does not improve after two days is to move to a lower elevation where oxygen saturation is higher.