Seretide (salmeterol xinafoate/fluticasone propionate) is a combination asthma medication. It delievers 2 medications (according to their website) .
The same medications are also in the Advair discus. Which is a dry powder inhaler. They are maintenance drugs. Albuterol is as needed because its a rescue drug (quick acting).
I have not heard of seretide or advair in the nebulizer form.....
best wishes.
~ when in doubt ask your doctor.