Illinois Medical Malpractice: The Most Common Causes

 Posted on November 21, 2025 in Personal Injury

When you walk into a doctor’s office or a hospital, you expect professional, skilled care. Unfortunately, across the state of Illinois, thousands of patients experience preventable medical errors that can leave them with worsening symptoms, new injuries, permanent disabilities, or worse.

Medical malpractice remains one of the most complex and emotionally charged areas of Illinois injury law. While each case is unique, certain types of mistakes occur far more often than others, from misdiagnoses to surgical errors. When these errors rise to the level of negligence, victims face long-term complications, financial losses, and life-altering injuries.

Understanding the top causes of medical malpractice claims in Illinois can help you recognize whether negligence played a role and whether you have a legal claim to recover damages. If you believe you are the victim of medical negligence, it could be time to speak to an experienced Arlington Heights, IL medical malpractice attorney.

What is Medical Malpractice Under Illinois Law?

Under Illinois statute 735 ILCS 5/13-212, a person who is injured through medical negligence has two years from the date he or she knew or should have known of the existence of an injury due to medical negligence, but in no event shall such action be brought more than four years after the injury occurred.

Medical malpractice occurs when the standard of care deviates from accepted standards. This means that if a similarly trained medical professional, given the same set of circumstances, would have acted substantially differently, then medical negligence may be present. Medical malpractice can include acts or omissions, such as providing the wrong medication or failing to follow up on a patient’s condition. Illinois requires an expert’s affidavit (735 ILCS 5/2-622) to confirm that malpractice may have occurred.

What Are the Top Causes of Medical Malpractice Claims?

Medical errors are a leading cause of death across the United States, with estimates ranging from 250,000 to 400,000 deaths per year. Despite this, medical malpractice claims are relatively rare, accounting for only about 1 percent of all medical errors. The primary causes of medical malpractice claims include:

Misdiagnosis or Delayed Diagnosis

The number one cause of malpractice claims includes misdiagnosis and delayed diagnosis. This can encompass a failure to order appropriate tests, misreading imaging or lab reports, or delaying a diagnosis of cancer. Attributing a patient’s symptoms to a less serious condition can result in missing evidence of heart attacks, strokes, infection, or other serious illnesses.  

Surgical Errors

Surgical mistakes can include operating on the wrong site, leaving instruments or sponges inside the patient, and nerve damage. Anesthesia mistakes (too much or too little) are also a common cause of surgical errors, along with failure to prevent infection and lack of monitoring during recovery.

Medication Errors

Medication issues are common in hospitals, clinics, and pharmacies. Medication issues can include prescribing the wrong medication, incorrect dosage or frequency, failing to check for drug interactions, ignoring documented allergies, and pharmacy dispensing errors.

Birth Injuries and Labor/Delivery Negligence

Birth-related negligence can often lead to lifelong consequences. The most common birth injury claims involve delayed C-sections, failure to monitor fetal distress, and improper use of forceps or vacuum tools. Shoulder dystocia, hypoxic brain injury, and maternal complications that are ignored or mismanaged are also common.

Emergency Room Errors

Mistakes can happen quickly in an ER because of the fast-paced environment. Some of the most common ER errors include misdiagnosed strokes or heart attacks, failure to treat sepsis, sending patients home too soon, overlooking critical symptoms, and inadequate medical history review.

Failure to Follow Up or Monitor

Many malpractice cases arise long after an initial appointment. This could be due to test results that were never reviewed, abnormal findings that were not communicated to the patient, failure to monitor a patient after surgery or treatment, or failure to recommend a specialist.

Contact a Cook County, IL Medical Malpractice Lawyer

While not every bad outcome is malpractice, many injuries result from clear deviations from the accepted standard of care. Speaking with a highly skilled Arlington Heights, IL personal injury attorney from Dickler, Kahn, Slowikowski & Zavell, Ltd. ensures the best possible outcome for your medical malpractice claim. Our firm has more than 150 years of combined legal experience. Call 847-593-5595 to schedule your initial attorney meeting.