Traveler's dust

Traveler's dust was a deadly, addictive drug. Those that used traveler's dust were said to be "walking the crimson road".

Description
Traveler's dust was transported and sold in the form of tiny roseate crystals, each a bit bigger than a grain of salt.

After the crystal was dissolved on the user's eye, it left the user's sight with a red-hazed vista of breathtaking clarity. While the addict was striding the crimson road, all sorrows sank beyond recall, while all joys were raised like blazing stars. The user felt transfigured, alive, and potent.

Use
Traveler's dust was used by dropping a single grain of the drug onto the eye and letting it dissolve.

Symptoms
Anyone using traveler's dust showed these telltale signs: trembling hands sometimes slurred speech, and&mdash;most telling&mdash;eyes the color of blood.

If the users were deprived of the addictive substance, the resultant death was an awful thing to behold. Deprived walkers invariably became violent, first toward others, then to themselves.

Source
One of the theories of the dust's origin held that it was the crystallized blood of a demon or a divinity.

History
Traveler's dust appeared a couple of years after the Spellplague of 1385 DR.

Some cities banned the sale of dust and placed its users in secure cells where they could reach their journeys' end in peace if allowed to keep their supply of dust.

Realmslore
Traveler's dust was illegal in most civilized places.