At that time, a new prescription is necessary and any unused refills cannot be filled. Plan ahead to get the quantities you need. Note the expiration date on all medication packages. Do not use any medications after they expire. Temperature changes and humidity can cause medication to become ineffective or dangerous.
Humidity can cause a tablet to become moist and powdery.
Do not store medications in places with high humidity, like gym lockers, bathrooms and above the stove. Do not store medications in the glove compartment of your car. The temperature can range from -20oF to 120oF. When too cold to too hot, your MDI will not deliver a good spray and may burst. Check your MDI label for the recommended temperature range. When you travel, make sure you have more than adequate supply of medications.