The next day you call in sick to work could be your last. However, a company probably won't terminate you due to excessive absenteeism for illness if you have a legitimate medical condition. Federal and state laws protect most workers from discrimination arising from medical conditions. You still need to consult your employee handbook to determine your company's sick leave rules when state and federal laws do not apply.

Sick Leave

A company can terminate an employee due to excessive sick days as long as federal or state law does not protect him. The Family and Medical Leave Act requires employers to give workers up to 12 weeks in unpaid sick leave for certain illnesses, serious medical conditions and a change in the family -- including the birth and care of a newborn, caring for a newly appointed foster child or caring for a family member with a serious health conditions, such as cancer.

Company Policy

When the FMLA, or a similar state statute, does not apply to a workplace situation, the law defers to the employee handbook. For instance, some employers allow a certain amount of sick days without question. Other businesses might require a doctor's note or may not allow any sick days. Unless the medical condition and subsequent employer action constitute potential case of discrimination, such as firing a pregnant woman, the company can fire an employee for failing to come to work due to illness -- assuming company policy does not allow sick days -- according to the U.S. Small Business Administration.

Discrimination

Employers must be careful about firing someone for taking too many sick days because this might count as discrimination. The Americans with Disabilities Act requires employers to offer reasonable accommodations before the company can terminate a disabled person. Some diseases, such as HIV and AIDS, count as a disability. If an employee frequently needs days off for doctor visits, allowing extra days of unpaid leave might be a reasonable accommodation. For instance, if an employer normally allows 10 days of unpaid sick leave, an employee needing an extra five to take care of a chronic illness counts as a reasonable need for the employee, according to the Equal Employment Opportunity Commission. Taking 100 unpaid sick days, however, qualifies as unreasonable.

Considerations

Companies must conduct a thorough investigation before terminating an employee for taking too many sick days. The employee should review company sick leave policy and request a leave of absence if he needs an extended period of time to get better. Also, he should go to a doctor for written proof of the illness and consult the human resources department about the company's sick leave policy and his FMLA rights. Failing to call in sick or provide a doctor's note usually negates the employee's right to equal treat under the law for medical leave. An employee must work 1,250 hours for a company before FMLA coverage applies.