What should i do if a pharmacy gave me someone elses prescription that made me take a trip to the hospital ?

You could probably sue to recover your damages -- medical costs and the value of puking, but the court or jury will also consider your own negligence in failing to read the label. In some states, if your own negligence amounts to 50 percent of the fault, you recover nothing. In other states, the damages are reduced by the percentage of your own fault. You could anticipate spending many thousands of dollars and could expect to recover many hundreds of dollars.