For many years my go-to liqueur when feeling ill has been Chartreuse, but it seems that there is now a global shortage. Does anyone have recommendations for an effective alternative? Benedictine? Jagermeister?

Polish blackberry brandy for bowel issues (Crohn’s disease, dysentery, colitis, IBS). 

This runs against conventional medical advice, but my 100 year-old grandmother swears by it (However, we secretly wonder whether there’s a more pedestrian motive in play).

Regular brandy for respiratory issues (chest cold).

Murphy’s Stout for attitudinal adjustment.

Hot red wine for chills.

Hot milk, honey, and butter for insomnia (can trade honey for Baileys Irish Cream).

For many years my go-to liqueur when feeling ill has been Chartreuse, but it seems that there is now a global shortage. Does anyone have recommendations for an effective alternative? Benedictine? Jagermeister?

Chartreuse is lovely! There was an article not too long ago that the monks decided to cut production for some reason; the article was blathering on about sustainability, but I'd think it was more about maintaining a better standard of quality than would be possible at too high a volume. I found some of the green label at half price clearance at the start of winter, seems it's not an appreciated drink around these parts. Their loss.

Alternatives, depending on what ails you, could be Cynar (look for the big artichoke on the label) or Fernet Branca. Both are bitters. Another with a similar dark-herbal base but smoother, sweeter, and a bit caramelized is called Averna. All of these would be digestives. If instead it's more of a cold or cough or congestion, a hot toddy will fix it: a good whiskey, honey, fresh lemon, cloves and/or cinnamon, top up with near-boiling water.

From my grandmother’s hometown…..warning: it may grow hair on your chest! 

For the truly adventurous there is always absinthe 

For the truly adventurous there is always absinthe

If the intent is to become absinthe-minded... an inadvisable R_x as per the Angelic Doctor (ST II II, Q 150, Art. 2, co.)  

I answer that, The sin of drunkenness, as stated in the foregoing Article, consists in the immoderate use and concupiscence of wine. Now this may happen to a man in three ways. First, so that he knows not the drink to be immoderate and intoxicating: and then drunkenness may be without sin, as stated above (Article 1). Secondly, so that he perceives the drink to be immoderate, but without knowing it to be intoxicating, and then drunkenness may involve a venial sin. Thirdly, it may happen that a man is well aware that the drink is immoderate and intoxicating, and yet he would rather be drunk than abstain from drink. Such a man is a drunkard properly speaking, because morals take their species not from things that occur accidentally and beside the intention, but from that which is directly intended. On this way drunkenness is a mortal sin, because then a man willingly and knowingly deprives himself of the use of reason, whereby he performs virtuous deeds and avoids sin, and thus he sins mortally by running the risk of falling into sin. For Ambrose says (De Patriarch. [De Abraham i.]): "We learn that we should shun drunkenness, which prevents us from avoiding grievous sins. For the things we avoid when sober, we unknowingly commit through drunkenness." Therefore drunkenness, properly speaking, is a mortal sin.

I have no intention of getting drunk, plastered or what have thee! 

Absinthe I would be content just to sniff it

My health normally is quite adverse to alcohol. Rare is the imbibing.

Drambuie in an iced tea mixture is ok, but it is indeed too sweet.
Unless you want to drown strawberries in it 

Polish blackberry brandy for bowel issues (Crohn’s disease, dysentery, colitis, IBS). 

This runs against conventional medical advice, but my 100 year-old grandmother swears by it (However, we secretly wonder whether there’s a more pedestrian motive in play).

Regular brandy for respiratory issues (chest cold).

Murphy’s Stout for attitudinal adjustment.

Hot red wine for chills.

Hot milk, honey, and butter for insomnia (can trade honey for Baileys Irish Cream).

Blackberry brandy has a scientific basis and does, indeed work.  The roots of blackberry contain a compound known as loperamide.  If you go to the drug store and look at the active ingredient of Imodium, for diarrhea and gas, you’ll see for yourself!  
For fever and headache, Absinthe may be used in moderation, for adults only, and DO NOT USE IF YOU TAKE A BLOOD THINNER!  Also, do not use otc blood thinners within four hours before or after Absinthe.  These include aspirin, ibuprofen, and naproxen. Acetaminophen should be avoided with all alcohol due to its effect on the kidneys.