A pilonidal sinus or pilonidal cyst is a tiny hole or tunnel that occurs in the perianal region. The hole is usually filled with hair, dirt, and skin debris. A pilonidal cyst is typically located at the top of the buttocks, at the junction of the tailbone and the cleft. 

The pilonidal cyst is typically caused when the hair punctures the skin and then embeds it. Infection of a pilonidal cyst results in an abscess that is very painful. The infected cysts might ooze pus and blood accompanied by a foul odour. A small incision is made to drain the cyst, or it can be surgically removed. 

Young men are most likely to be affected by pilonidal cysts, and they tend to recur. Those who spend long periods of time sitting are at an increased risk of developing this condition. Dr. Karunakar Reddy, Gastroenterologist at Matrusri Hospital Hospital, says that diagnosing and treating this pilonidal sinus can help in preventing it from getting serious.

Symptoms of a Pilonidal Cyst

If you experience the symptoms mentioned, consult a doctor immediately.

  • Sitting often makes the pain worse.
  • The area between your buttocks is swollen.  
  • There may be redness and tenderness in this area.
  • PUS or blood draining from an abscess and it may have a foul odour.
  • Hair poking out of the lesion.
  • Nausea, fever and fatigue.

Causes of Pilonidal Sinus

Though its cause is not known exactly, many believe it’s caused by hormonal changes (since it mostly happens after puberty), the growth of hair in that area, friction caused by garments and sitting for a longer time.

If the hair growing in the area is forced back under the skin due to certain activities that cause friction like prolonged sitting, it results in this condition. In the same way that an immune system reacts to a splinter when it encounters a foreign object, the body considers this hair to be a foreign object. As a result, the body forms a cyst around the hair. Occasionally, a person might have more than one sinus that is connected under the skin.

Treatment for Pilonidal Sinuses 

Conservative treatment

The treatment for this condition is based on the severity of the condition. The disease can be treated with antibiotics if it is detected early and without any pain or inflammation. Remember that antibiotics cannot heal the sinus tract, but provide relief from symptoms like an infection. You need to attend follow-up visits regularly to remove the hair and clean the area. Pay more attention to hygiene.


In this procedure, the abscess is opened using a scalpel to drain the pus & blood and clean away any hair, debris inside the abscess. It is then allowed to heal from the inside out. In most cases, the wound will heal in a few weeks, and there is no need for further treatment.

Phenol injection

The doctor will then inject phenol into the cyst, an antiseptic chemical compound when you are under local anaesthesia. One may have to undergo the procedure several times. The lesion will harden and close as a result of this treatment.

The recurrence rate is very high for this procedure. Sometimes surgery is the best choice of treatment for this condition.


In case of recurrent pilonidal sinus or having more than one sinus tract, it is advised to undergo a surgical procedure.

The surgeon will open the sinus tract under local anaesthesia and remove all the pus, blood, hair and debris. After this process has been completed, the wounds are stitched up and allowed to heal.

Laser therapy

When hair is removed by laser therapy, it can prevent them from becoming ingrown and causing pilonidal cysts to recur.