The combined effect of alcohol and drugs can cause unexpected symptoms. A Pennsylvania woman arrested and prosecuted for driving under the influence (DUI) recently tried to avoid conviction by claiming that she became unexpectedly impaired when a pain “patch” that she was wearing heightened the effects of her alcohol intake. She admitted that she had failed to read the pain patch label, and claimed that her doctor did not advise her to avoid alcohol while using the patch.
Pennsylvania has not yet formally recognized the defense of “involuntary intoxication.” Several other states have identified certain circumstances where a person’s impairment may be excusable. These circumstances include where the intoxication was caused by force, duress, or fraud, and where the intoxication was an innocent mistake. An innocent mistake can occur when a person takes an alcoholic drink or a narcotic pill under the mistaken belief that the drink is nonalcoholic or that the pill is a simple aspirin. Excusable circumstances found by other states also include occasions where the person suffers an unexpected overreaction to a legal intoxicant or has an unexpected impairment from a properly prescribed drug.
Pennsylvania courts have announced that if the defense of involuntary intoxication is to be adopted in Pennsylvania law, our legislature should address the issue. The courts have also observed that defendants will have the burden of proving the defense. In the case involving the woman who used the pain patch, the trial court and the appeals court rejected the woman’s defense largely because she did not call expert witnesses and failed to prove that her reaction was unique, unusual, or unexpected.
While taking prescription or over‑the‑counter drugs, be sure to avoid any substances, including alcohol or other medications, that could render you impaired. Unless your physical reaction to a combination of drugs and alcohol is documented as highly unusual, you cannot raise involuntary intoxication as a defense to DUI charges.