Is it safe to give my 10yo with mild asthma albuterol inhaler that expired 1 year ago?

No, because: It is important that you have constant access to asthma medication for your child, especially in preparation for when a child travels or misplaces an inhaler. If the only available inhaler is one that expired a year ago, you don't know how empty it is or how effective the medication inside is. Speak to your primary care provider asap and obtain new inhalers.
Maybe. The inhalers slowly leak medicaion so if he isn't improving any with one threatment you need to get a new one.
Probably. Pharmacology today states many drugs are still effective after the expiration date ; with the exception of the antibiotic tetracycline. The medication may not be "full strength" any longer, but it should generally be safe for short term use or mild conditions. Severe asthma can be a life threatening medical emergency in a small child. Contact your physician if in doubt.

Related Questions

I'm having a mild asthma flare-up. Flovent and Ventolin inhalers are expired for 2 years. Ok to use? I can't go to the doctor until 2 weeks later.

Call or go to ER. Don't ignore asthma, can be a deadly mistake. Call a doctor that has treated you in the past in order to get medication to bridge to the appointment. This may be possible depending on circumstances. Otherwise, go to urgent care or to the ED. Using expired medication may be life saving in certain circumstances, but no substitute for an evaluation by a physician and up to date planning. Read more...