Final answer:
To calculate the amount of Atarax 40mg needed, divide the dose by the concentration to determine the volume in milliliters.
Step-by-step explanation:
To calculate the amount of Atarax 40mg needed, we can use the formula:
Dose (mg) = Concentration (mg/ml) x Volume (ml)
Given that the concentration is 50mg/ml and the desired dose is 40mg, we can rearrange the formula to solve for Volume:
Volume (ml) = Dose (mg) / Concentration (mg/ml)
Plugging in the values:
Volume (ml) = 40mg / 50mg/ml = 0.8ml
Therefore, you would need to give 0.8ml of Atarax.