Hi. It appears to me that the Lower respiratory tract infection (LRTI - suggestive by coughing with phlegm) that your are recovering from has created some injury and swelling on your vocal cords. Since you lost your voice all the way down to a whisper, it may be laryngitis as well. This may have been possible because of the infective phlegm that you cough out has inflamed the vocal cords and the neighbouring region. The cough in turn causes more vocal cord injury and throat irritation making your throat sore. If it is possible for you to rest your voice for upto 24 hours (ideally 48) then that will help the vocal cords heal remarkably. If you do need to speak then use short sentences and speak in a normal tone. Do not whisper as it creates more damage to your vocal cords. Voice rest reduces vocal cord movements and allows healing. When you speak the cords vibrate and the swelling persists. If you have cough then an antitussive lozenges can reduce it as much as possible but in your case since you have phlegm produced in your lungs, an antitussive will prevent the phlegm from coming out and worsen your LRTI. Thats why you are on an expectorant and this will increase your coughing but help you get rid of the phlegm. I would recommend getting rid of the phlegm as a bigger priority than reducing vocal cord injury due to coughing. This situation may prolong your hoarse voice by a few days. In addition, it is recommended that you take sips of normal or lukewarm water every 30 minutes to keep your throat moist and well hydrated. Avoid gurgling as it precipitates a lot of movement in your throat. Adding a good antacid (Cap Pantoprazole 40 mg once in the morning 15 minutes before meals) and an anti inflammatory + anti edema tablet (paracetamol/diclofenac + serratiopeptidase) can help speed your recovery. If your voice does not return to normal or improve significantly after 24 hours of absolute voice rest then you will need to visit an ENT specialist for a laryngeal endoscopy to assess your vocal cords. The improvement will also be minimal if you do not honestly rest your voice and put up efforts half heartedly. Do keep me posted on your recovery. Treatment is an iterative process so do give me the chance to make modifications to the management if your recovery is tardy. This can help me tailor the treatment best needed for you.