extendryl g is guiafenesin and phenylephrine-loosens secretions and shrinks blood vessels in mucous membranes/decongestant

Sambucol elixir-elderberries?check with local herbalist

Mucinex d-guiafenesin and dextromethorphan-see above+cough supressant, DM overuse causes sedation/hallucinations called robi-tripping.

Sudafed-pseudoephedrine, or chlorpheniramine maleate, see phenylephrine above

Theraflu- acetaminophen, chlorpheniramine maleate, dextromethorphan, and pseudoephedrine.

IMHO:

Ditch the mixtures, keep the elderberries if they work for you.
acetaminophen/ibuprofen for pain
Guiafenesin +big glass of hot water+hot shower to empty clogged sinuses or get stuff out of lungs: next person to use the shower will not thank you.

sudafed or chlorpheniramine or phenylephrine for a runny nose. Don't mix em, don't overmedicate, they all have rebound issues and using too much or for too long will make the congestion worse. BTDT.

dextromethorphan to stop a dry cough or to let you sleep.
benadryl at night to reduce runny nose and sleep.

Buy them in separate pill form, so you don't take something you don't need just cuz its all in one bottle.

Honey, lemon and bourbon for severe cough, dry throat, loneliness, weltschmerz, ennui...or just cuz.