Is it safe to take medications containing alcohol while I am pregnant or breastfeeding?

Better off without. Almost every alcohol-containing medication now has substitutes that are alcohol-free. Talk to your pharmacist. There is no safe amount of alcohol during pregnancy, although the likelihood of very occasional exposures to the very small amounts of alcohol in medicines taken in proper doses is unlikely to cause harm. Alcohol is transmitted to breast milk, and babies are tiny. Find alcohol-free meds.
No. Alcohol should be avoided during pregnancy whether it is an alcoholic beverage or an alcohol containing medication. There is not an established "safe" level of alcohol consumption in pregnancy, so the recommendation is to avoid it all together.