There is no adequate translation of tonic wine in Spanish, probably so that the phrase won't get confused with tonic water. About the nearest thing is bitters, and while there are many types of bitters, from rhubarb to chocolate via celery, Angostura is the nearest the English speaker will get to the original product, in that funny little bottle with the oversize label.
But tonic wines have a long and interesting history, although they have not always been viewed in a favourable light. The best-known, Buckfast, is unjustly known as a drink that satisfies the demand for a cheap and highly alcoholic pick-me-up, or lay-me-down, with the tag line when things go wrong of 'Blame it on the Bucky'. In truth such potions took over from red wine in the mid-1850s, prior to which Bordeaux was believed to be especially good for 'children and literary persons', and 70 year ago Australian wine suppliers advertised their products as 'natural tonics'.
Prior to that 'coca wines' were mixtures of fortified red wine and coca leaf.
However, it soon became apparent that there was no such thing as a genuine tonic wine, and Buckfast is the sole survivor. The label states it offers no health benefits. Created by Benedictine monks in the 1880s, it is fortified red wine with added caffeine, as well as some secret ingredients. Amazingly, sales have reached $60 million annually. Tonic wines were sold in British pharmacies but they're hard to find today - probably no great loss to the modern drinker. Some things are best resigned to history.
The Jerez bodega of Caballero produced the first genuine Spanish liquor, again with the obligatory secret recipe 185 years ago and 25º alcohol. Most Jerez bodegas marketed a 'ponche' at some time or another.