GlaxoSmithKline and Alphapharm had agreed to a voluntary recall of the Ventolin and Asmol inhalers – some of which were only delivering a third of the normal dose.

The Therapeutic Goods Administration said on Monday that some patients may need to take extra doses of their medication, if it was in a faulty batch.

The affected Ventolin batch numbers are KN7170, KN7173, KN7178, and KN7179, and the Asmol batch numbers are KL6790, KL6795, KL6796, KL6797, KL6798, and KL6799.

The pharmaceutical companies estimate that up to 50,000 inhalers from the affected batches are experiencing the problems, which are related to the delivery mechanism for the medication.

The Acting Chief Health Officer of NSW, Tony Penna, said people who used the inhalers should check the batch number by removing the canister from the plastic tube, where they will find the batch number on the bottom of the canister label.

“If they identify that they have one of the affected inhalers, it can be returned to their pharmacy for a free replacement,” Dr Penna  said. "Should people using the affected batches of Ventolin or Asmol inhalers experience a worsening of their asthma or have concerns about the use of their inhaler they are advised to seek immediate medical attention."

He said that due to limited access to medical services over the Christmas and New Years period, asthma sufferers and their carers should ensure they knew what medical services were available over the coming week.

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