give information about asthma inhalers(no wikpedia)

Inhalers have transformed asthma treatment. They enable children and adults with asthma to deliver medicine directly to their lungs nearly anytime and anywhere. A variety of inhalers are available to help relieve or control asthma symptoms. Two common types include metered-dose inhalers and dry powder inhalers.

Use of this asthma inhalers:
To begin, shake the inhaler five or six times.
Remove the mouthpiece cover and place the spacer over the mouthpiece at the end of the inhaler.
Put your lips and teeth over the spacer and breathe in slowly. As you do so, squeeze the top of the canister once. Keep inhaling even after you finish the squeeze. Continue inhaling slowly and deeply.
After inhaling, remove the spacer from your mouth and hold your breath for up to 10 seconds.