What your husband has is nasal allergy, possibly due to some indoor agent like mold or house dust mite. The best treatment is to clean up the house once and air the mattresses. Till that is done you can take an allergy pill like Fexofenadine 180 mg once daily. The drug is not a cure, its only to counter the allergy. Avoiding is the best treatment.
Next Steps
If still persistence after meditation consult an ENT specialist online or nearby
Health Tips
1. Keep an allergy diary, with exact date time and location and what was he doing just before the episode started. Do write down and then analyse.