On Saturday, Farquhar underwent surgery to address the aneurysm. The surgery was "successful," the White Sox said in a statement.
Farquhar, who remains in critical condition at RUSH University Medical Center, has use of his extremities, is responding appropriately to questions and commands and is speaking to doctors and his family.
He is in neurologically stable condition in the ICU unit at RUSH, the team said. He is expected to remain in the neurosurgical ICU at RUSH for the next few weeks.
Farquhar's wife, Lexie, and family members are at the hospital. While the family appreciates the outpouring of support, the White Sox asked the public to respect the family's privacy.
The team said they will provide updates on his health, as appropriate.
Fans interested in sending "Get Well" wishes and letters of support to Farquhar should address mail to him at Guaranteed Rate Field, 333 W. 35th Street, Chicago, IL 60616.
Statement on Danny Farquhar.— Chicago White Sox (@whitesox) April 21, 2018
White Sox fans, please keep Danny and his family in your positive thoughts and prayers. pic.twitter.com/4DdwnXbVXd
Don't miss these warning signs
An aneurism "resembles a small blister, a pimple that grows off the side of a blood vessel," explained Dr. Babak Jahromi, a professor of neurosurgery at Northwestern Memorial Hospital.
He said those blisters usually take years to grow large enough to burst, often undetected. But when they do, blood leaks in the brain. That damage and pressure inside the skull, Dr. Jahromi warned, could be lethal.
"If the bleeding doesn't stop, the patient doesn't survive beyond a couple of minutes," he said.
High blood pressure, smoking, polycystic kidney disease, and a family history of aneurysms put you at a higher risk of having an aneurysm, Dr. Jahromi said.
While doctors don't fully know what causes an aneurysm to develop or burst, Dr. Jahromi explained, there are symptoms to look out for once they rupture. So if you think you have an aneurysm, you can hopefully seek medical treatment in time.
- Severe headaches
If your family has a history of aneurysms or you are experiencing new headaches, you should seek medical advice and screening, Dr. Jahromi recommended.
Dr. Jahromi said about a third of those whose aneurysms burst will make a full recovery.