The most important thing is WATER.
For Mucinex to work properly you need to be hydrated.
Your body needs water to thin the mucus.
Keep in eye on your urine for signs of dehydration.

I take 2400 mg per day... 2 600 mg pills when I get up, and 2 600 mg pills late in the evening. I also take Breztri twice per day, with no problems...

@MichealZerjav use the blue and white mucinex 600 mg twice a day. I take it same time I do my Breztri. Cuz both get taken every 12 hours. 6am and 6pm and I drink a lot of water. Right now I’ve been coughing a lot too so maybe I’ll try the DM one
I was just contacted by the Mayo Clinic bout a clinical trial. Called Airflow4 targeted lung degenerative. He says he’s done this test before phase 2 and 3 and he thinks it will help w my breathing and mucus. I’m waiting to hear when I can start the testing. I trust this doctor fully and Mayo Clinic is very reputable. I’ll keep u updated. Check out the trial on AI. Sounds promising to me

Dextromethorphan is a cough suppressant for a person experiencing phlegm accompanied with an irritating cough.
I do not have a cough just the phlegm accumulation so I was told not to use it just to use time release formula. regular mucinex

Pulmo recommended it to me once. When I feel a little congested, I take one for a couple of days. It works best if I drink plenty of water with it and exercise. But it makes me sleepy and draggy, so it's not usually worth it to me. Curious about what DM means.