Three Centuries Of Discovery
History of absence seizures
From the earliest written accounts in the 1700s to the treatments used today.
17th – 18th Centuries
Early clinical descriptions
The earliest known written accounts of what we now recognise as absence seizures come from the early 1700s.
1705
The French physician Poupart described brief episodes in which a person suddenly lost awareness for a short time and then resumed activity as if nothing had happened.
1770
Swiss physician Samuel-Auguste Tissot provided a clearer and more influential description. He wrote about a young patient who had frequent short episodes marked only by an instantaneous loss of consciousness, sometimes with a slight movement of the eyes. After the episode the child would often continue the sentence she had been speaking, or sometimes forget what she had been saying. Tissot called these petits accès ("little attacks").
These early observers recognised that the episodes were epileptic in nature but did not yet have a specific name or understanding of their mechanism.
19th Century
Naming and classification
The 19th century brought clearer terminology and attempts at classification.
1824
French physician Louis Florentin Calmeil, who worked in the large Paris asylums (Salpêtrière and Charenton), introduced the term "absences" in his doctoral thesis. He used it to describe the sudden, brief interruptions of consciousness he observed in patients.
1838
Jean-Étienne Esquirol coined the term "petit mal" ("little illness") to distinguish these milder episodes from the dramatic convulsions of "grand mal." The term quickly became widely used, although it was often applied too loosely to any mild seizure.
1854
Delasiauve ranked absences as the least severe form of epilepsy and helped develop the idea of idiopathic epilepsy (epilepsy without an obvious structural cause).
1861
Reynolds preferred the Latin term epilepsia mitior ("milder epilepsy") and gave one of the most thorough clinical descriptions of the time.
Late 19th / Early 20th c.
Physicians such as Otto Binswanger (1899) and William Gowers (1901) emphasised careful observation of subtle non-motor seizures that could easily be missed or dismissed as daydreaming.
Early 20th Century
The concept of pyknolepsy
In the early 1900s the term pyknolepsy (from the Greek pyknos = dense, frequent, or packed together) was introduced to describe the very frequent, short, stereotyped absences typical of many children.
At first there was debate about whether pyknolepsy was truly a form of epilepsy. Some doctors thought it was a separate benign condition because the children usually developed normally and the seizures often stopped in adolescence. It was only with the arrival of EEG that it was firmly established as an epileptic disorder (by the mid-1940s).
1920s – 1940s
The EEG revolution
This was the most important scientific breakthrough in understanding absence seizures.
1920s – Early 1930s
German psychiatrist Hans Berger invented the electroencephalogram (EEG). He made the first recording of an atypical absence seizure (results published in 1933).
1935
A team at Harvard Medical School led by Frederic Gibbs, Hallowell Davis, and William Lennox published the landmark finding that typical absence seizures are accompanied by a highly characteristic 3 cycles-per-second (3 Hz) spike-and-wave pattern on the EEG. This pattern starts and stops abruptly and is usually seen over both sides of the brain at the same time.
The discovery of the 3 Hz spike-and-wave pattern:
- Confirmed that absences were genuine epileptic events.
- Allowed doctors to distinguish them clearly from daydreaming, attention problems, or other types of seizures (especially temporal lobe seizures).
- Made accurate diagnosis possible for the first time.
William Lennox went on to describe the “petit mal triad” (absence, myoclonic, and akinetic seizures) and helped establish childhood absence epilepsy as a distinct syndrome.
Treatment
Development of specific treatments
Before the mid-20th century, there were no reliable medications specifically for pure absence seizures. Earlier drugs such as bromides (used from the 1850s) and phenobarbital (from 1912) could help with convulsions, but they were largely ineffective against absences.
1940s
Trimethadione (Tridione / Troxidone) — the first drug shown to be specifically effective against absence seizures. It was discovered while researchers were searching for better painkillers. Although it worked, it caused significant side effects, including night blindness, blood disorders, and kidney problems. Safer alternatives were urgently needed.
1958
Ethosuximide (Zarontin) — developed by Parke-Davis as a safer member of the succinimide family. It entered clinical use in 1958 and was approved in the United States in 1960. Ethosuximide remains one of the preferred first-line treatments for pure absence seizures because of its good effectiveness and relatively favourable side-effect profile compared with earlier drugs.
Early 1960s
Valproic acid / Sodium valproate — its anticonvulsant properties were discovered by accident, when a French researcher testing other compounds dissolved in valproic acid realised the solvent itself had strong anti-seizure effects. Clinical trials began in the early 1960s; it was licensed in France around 1967 and became available across Europe in the late 1960s. Approval in the United States came later, in 1978. Valproate was especially important because it could control both absence seizures and other generalised seizure types.
1990s onward
Newer options — Lamotrigine (introduced in the early–mid 1990s) and Levetiracetam (late 1990s) — expanded the range of treatment choices, particularly when side effects needed to be avoided or when other seizure types were also present.
At A Glance
Summary timeline
1705–1770
First clinical descriptions
1824–1838
Terms "absences" and "petit mal" introduced
1935
Characteristic 3 Hz spike-and-wave EEG pattern identified
1940s
First specific drug (trimethadione)
1958–1960
Ethosuximide becomes available
Mid–late 1960s
Valproate introduced in Europe
1978
Valproate approved in the United States
1994
Lamotrigine launched as Lamictal for the adjunctive treatment of partial seizures
1999
Levetiracetam approved as Keppra for adjunctive treatment of partial-onset seizures in adults