Glass used for effervescent paracetamol ????

I assume that what you've got is a sort of whitish bloom on the glass that can't be removed.

Nothing to do with the paracetamol. Most dishwasher detergents will etch older or cheaper types of glass. There's not much you can do about it now, other than remember to hand-wash you glasses in future.

Most tableware these days (plates, cups, mugs etc) has a dishwasher-proof glaze, but older tableware, say pre-1950, possibly a bit later, will be etched and the surface will go whitish to opaque.

In message , Jethro_uk writes

We have a similar glass, but I have always assumed that the glass has been marked by a spoon used for stirring.

No, it's not dishwasher etch ... the two identical glasses washed at the same time came out spotless (all 3 were purchased as a set ....)

It looked for all the world like little spots of sugar have stuck to the glass. Washing by hand removed them, but left the water "lying funny" on the glass ? (You know the way alcohol behaves differently to water in a glass ?)

Ah, ... well a spoon was used ????

That's the key ...

It is probably some sort of powdery surfactant used in the dispersal of the paracetomol - the effervescence is a fruit acid and bicarbonate and I can't think that would damage even the finest glassware.

The only things that really attack glass are caustics and hydrofluoric acid - neither of which are likely in a potable medicine.

OTOH commercial dishwashers all bets are off - the raw dishwasher detergent for them is 12% sodium hydroxide with a trace of stainless steel corrosion inhibitor in. That will go for fine glassware. Domestic dishwasher will eventually cause surface damage.

You can polish it out with a lot of elbow grease and cerium oxide if it is dishwasher hazing.

spray with descaler: may be chalk..

Or try vinegar - preferably white.

Brexiter. I suppose Old Etonians would insist on wine vinegar.

Seriously, common or garden brown malt vinegar will rinse off without leaving a trace.

FYI, other than paracetamol, these are ingredients of paracetamol effervescent tablets:

Anhydrous Citric Acid Povidone Sodium Hydrogen Carbonate Saccharin Sodium Anhydrous Sodium Carbonate Simeticone Polysorbate 80 Aspartame

And these are for soluble (non-effervescent) tablets from different manufacturers:

Sodium bicarbonate Sorbitol powder Saccharin sodium Sodium lauryl sulphate Citric acid (anhydrous) Sodium carbonate (anhydrous) Polyvidone Dimeticone

Citric acid Sodium sulphate Lactose monohydrate Sodium hydrogen carbonate Povidone Simethicone Saccharin sodium Lemon flavour, containing citral, citric acid, ethyl alcohol, lemon oil, lime oil, alpha-tocopherol, triacetine, maltodextrin, gum arabic and sucrose Macrogol 6000

I can't see any of the above causing the effect you have described, BICBW.

I'd be worried about the innards of the person drinking it, with all these stories of counterfeit drugs recently. Brian

Is that to please Harry ;-)

Van der Waals forces between the excipient substance and the glass wall? I never get this problem, despite heavy use of fizzy painkillers, but I do all my washing up by hand.

Four different kinds of artificial sweetener including Aspartame. Nice!