Hello,
Thanks for posting your query.
From the history it seems that your grandmother is having chronic bronchitis. Wheezing and impacted phelgem need systemic antibiotics to deal with the infection she is having in her airways. You will have to consult her physician to get the best antibiotic and brochodilators prescribed for her. Steroids- both oral and inhalers might be needed for symptomatic relief.
However the best treatment for impacted mucus is steam inhalation. Inhaling steam from a bowl of hot (but not boiling water) may help to soften, and loosen, the buildup of mucus in her airways. You may also find that adding some menthol crystals, or eucalyptus oil, to the water helps a lot. Other than that, avoid eating indigestible, spicy, foods and meats and let her eat simple wholesome foods. Out-of-door exercise, sunbaths also help a lot.
If she has fever or the cough is worsening then it is advisable to get a X-ray chest done to rule out pneumonia as well.

Hope this answers your query. I will be glad to answer the follow up queries that you have.
Please accept my answer in case you do not have further queries.
Wishing you good health.
Regards.
Dr. Rakhi Tayal.

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