Could you be giving your pet the wrong dose?
It was my first job as a pharmacist in Central Florida, and my technician at the time was also newly registered when he was handed a prescription for amoxicillin liquid for a child. He looked carefully at the prescription and somehow misinterpreted “tsp.” as tablespoonful instead of teaspoonful. If this medication had gone out like that, the child would have received three times the dose that the doctor intended for him to have. Doctors are now encouraged not to abbreviate common words, but nothing replaces experience and understanding of how certain medications are given in the prevention of errors.
One of the ways to prevent confusion in dosing is to understand the relationships between common terms such as milliliter, ounce, gram, teaspoonful, kilogram, cc, pound, and between the other different weights and measures. I will attempt to clarify some of these commonly used terms and hopefully make some sense of these often-prescribed doses.
To begin, let’s differentiate between solid dosage units such as tablets or capsules, and liquid dosage units such as suspensions or solutions. A dose describes the amount of medication that is supposed to be given at a particular time. Liquids are measured by volume (e.g. milliliter, teaspoonful, drops) and solids are usually measured by quantity or weight (e.g. milligram, tablet, and gram). Here are some of these relationships:
Often ml and cc are used interchangeably and measure the same amount of volume.
1 milliliter (1ml) = 1cc
5 milliliter (5ml) = 1 teaspoonful
15 milliliter (15ml) = 1 tablespoonful
3 teaspoonful = 1 tablespoonful
30ml = 1 ounce
1000ml = 1 liter
1000 micrograms= 1milligram (mg)
1000milligrams (1000mg) = 1 gram
30 grams = one ounce
1grain (gr.) = 65mg
Many times a prescription calls for ½ or ¼ of a tablet. It is important to note that not all solid dosage forms like tablets are designed to be split into pieces. Some long-acting formulations for example are designed to release the drug over a specific period of time. When those tablets are damaged by splitting them, the medicine can get released all at once, often causing potential for overdose. When you purchase a medicine, check with the pharmacist to make sure the medicine is safe to split. If the medication is safe to cut, using a tablet splitter will generally give the best results. Tablet splitters are found in most pharmacies and are relatively inexpensive compared to the cost of tablet loss, damage, or personal harm that can result in using fingers or a kitchen knife to cut the tablets.
When looking at the conversions above, we note that one teaspoonful is equal to 5 milliliters. Many doses are written as teaspoonful or tablespoonful. Although the accepted conversion is 5ml for a teaspoon and 15ml for a tablespoonful, if you use a spoon from your utensil drawer there could be a range from 3ml to 6 or 7 ml for a teaspoonful. Because of this, it is better to get a measuring syringe and give exactly 5ml or 15ml. Your 1-800-PetMeds pharmacist is a great resource and it is best to use their specialized knowledge in this area to ensure the dose that you are giving is the correct dose.
As always, if you have any concerns about your pet’s health it is important to make an appointment with the veterinarian who is the best position to ensure the proper diagnosis is made and the correct treatment is recommended. Having a good relationship with the veterinarian is one of the best things you can do to maintain the health of your pet.