What does 'gr' represent in pharmacological measurements?

In pharmacological measurements, 'gr' stands for grains, which is a unit of measurement traditionally used in medicine. One grain is equivalent to approximately 0.065 grams or 65 milligrams. This unit has been historically significant in the dosage of medications, especially in formulations predating the widespread adoption of the metric system. Grains are still found in some drug prescriptions and are particularly relevant in the context of certain medications, where precise dosages are critical, such as in the case of certain opioids or hormone therapies. Understanding that 'gr' refers to grains helps healthcare professionals accurately interpret medication dosages and ensures safe administration of drugs.