External hemorrhoids form when pressure builds in the veins near the anus. If that pressure suddenly spikes - from straining during a bowel movement, lifting something heavy, or even coughing - a small vein can rupture internally, trapping blood inside and forming a clot.
This clot (thrombus) stretches the surrounding tissue and nerves, which is what causes the sharp pain. Even though it can be very uncomfortable, the condition is self-limiting and usually resolves over time or with proper treatment.
Factors that can increase your risk include:
A thrombosed external hemorrhoid typically appears as a hard, purplish-blue lump near the anus. Symptoms often include:
The pain tends to peak within the first 48–72 hours and then gradually improves as the clot begins to shrink.
A proctologist can diagnose a thrombosed external hemorrhoid with a quick visual and physical examination. The best treatment depends on how recently symptoms began and how severe the pain is.
While home remedies can ease discomfort, professional treatment ensures the clot is properly addressed and complications are avoided.
If you experience sudden, severe anal pain or notice a hard lump that wasn’t there before, it’s best to see a proctologist right away. Early treatment can dramatically reduce pain and speed up recovery. Even if the pain improves on its own, follow-up care helps prevent future thromboses and keeps your recovery on track.