The pharmacist has a very important job because the pharmacist needs to protect you from drug interactions. Sometimes when you take two drugs at the same time, one drug can make the effect of the other drug stronger or make it weaker. This can be dangerous. Some people take blood thinners because they have heart problems. If you take a blood thinner like aspirin and some antibiotics, your blood will become very very thin. If you hit your arm and bruise yourself, your body will continue to bleed. It will be difficult to heal because your body won’t stop bleeding. The pharmacist knows about problems like this so the pharmacist will always ask you about all the medication you are taking.