It is not haram or unlawful to use such medications. Let me cite three points to support this ruling:

1- The alcohol added to the medicine has undergone a chemical transformation in such a way it is not intoxicant anymore. It is akin to alcohol turned into vinegar. While the former is haram, the latter is halal.

2- The amount of alcohol in the medicine is minuscule. As such, one excused since the Shari`ah stresses latitude and ease rather than strictness.

3- There is another rule known as `Umum al-balwa. Based on this, such products can be deemed halal.

According to this rule, if certain things are so commonly used in medicines in such a way it becomes hard to avoid it, then the rule of relaxation applies: Where there is hardship the rigor of laws is relaxed.

Based on these considerations, you are allowed to use the medication, if prescribed by a physician.