It’s worth repeating: you can’t harm someone by giving them naloxone. If someone hasn’t used an opioid, naloxone won’t do anything to them. Naloxone also can be used on minors or even pets if necessary.
If you’re still worried, you should know that naloxone has been used for years, in hospitals, by emergency medical responders, and by first responders like police and firefighters. The Food and Drug Administration first approved naloxone in the 1970s, and the consumer forms were approved in 2014 (Evzio) and 2015 (Narcan).
The naloxone you can get from a pharmacy also has been designed to be easy to dispense.