Ask Questions if Your Medicine is a Powder


A child's father went to the pharmacy to pick up a prescription for liquid amoxicillin, an antibiotic used to fight infections. The liquid form of this medicine starts as a powder that needs to be mixed with a specific amount of water by the pharmacist before use. By mistake, the pharmacist gave the child's father the bottle of medicine with just the powder.

The directions on the pharmacy label said to give 9 mL (about 2 teaspoons) of medicine for each dose. These were the correct directions for the medicine if it was mixed with the right amount of water. The child's father had a small plastic cup for measuring each dose. He filled the cup with enough concentrated powder to reach the 9 mL line and gave it to his child to take with a little water. The child actually got twenty times more medicine than the doctor ordered because the powder was not diluted. Nine mL of the powder would make 20 doses once it is mixed with the proper amount of water. After giving his child the first dose, the father thought something was wrong and called the pharmacy. The mistake was discovered and the medicine was mixed correctly and returned to the child's father. Fortunately, the child was not harmed.

How could the pharmacist forget to add the water to this powder medicine? Actually, it's quite easy to make this mistake and it happens from time to time. The pharmacist knows it is best to mix some medicines, including this one, with water right before it is picked up by the parent or caregiver. So, the usual process in most pharmacies is to put a label with the patient's name and directions for taking the medicine on a bottle that contains the correct amount of powder medicine. The medicine is then placed in a bag with a note on it to let the store clerk know that the medicine requires mixing by a pharmacist before it is given to the customer. Sometimes this message can be overlooked, especially if the pharmacy clerk is new, as in this case.

Always double check with your pharmacist before taking or giving a medicine if:

  • The medicine is a powder that you were told to take by mouth (swallow), but there are no directions on the label about adding water or another liquid
  • The medicine is a powder with directions to measure the dose in teaspoons, tablespoons, or mL (milliliters); these measures are used for liquid medicines
  • You expected a liquid medicine and you receive a powder medicine

These conditions suggest there could be an error. You will need to take the medicine back to the pharmacy. Do not try to add water to the powder yourself. The amount of water used must be carefully measured to be sure that each teaspoon has the correct amount of medicine in it. Opening the bottle and checking the medicine before you leave the pharmacy might help spot a mistake right away.

Created on June 13, 2012

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