Do not ignore a subpoena. The judge has the authority to order a contempt citation against a person properly served with a subpoena that does not respond. A money fine and a court appearance to defend the contempt charge are natural consequences that follow for someone that ignores a valid subpoena.
Challenge by Motion
If you have a valid challenge to what is sought in the subpoena you can make a motion to limit the scope or reach of the subpoena before you comply. For this you will be best served to use an attorney as your advocate before the judge to make such a challenge.