Post-acute withdrawal syndrome (PAWS)
Post-acute withdrawal syndrome or PAWS is a combination of symptoms that has been described with quitting a number of drugs, including alcohol, antidepressants, illegal drugs, and others. Acute withdrawal typically consists of the severe illness phase (flu-like), whereas PAWS would include less severe but disconcerting symptoms that persist after the acute phase is over.
These include (from this link):
Hostility or aggression
Anxiety, panic, or fear
Irritability and mood swings
Exhaustion or fatigue
Inability to sleep
Trouble concentrating or thinking
Loss of interest in sex
Anhedonia, or the inability to feel pleasure
Trouble with memory
Sensitivity to stressful situations
Although this has not to our knowledge been specifically associated with quitting caffeine, the symptoms reported by many people on caffeine forums are so similar that we strongly believe it is the same phenomenon. In particular, articles on PAWS and posts from those who have had difficult recovery from caffeine addiction both note that symptoms often come and go in waves. That is, you may feel better for a period of time, then have symptoms unexpectedly come back, sometimes just as bad as they were before. In our experience, this can be disconcerting when recovering from caffeine dependence, as it leads people to suspect there is something else wrong!
Some scientific research has been done on quitting caffeine use; however, the overwhelming majority of the best designed studies have only followed the participants for a few days or a few weeks. This is probably not surprising, as it would be extremely difficult to get a group of people (especially heavy caffeine users) to completely stop using it for an extended period of time and to verify their abstinence. One possibility is that many people resume using caffeine again after the period of acute withdrawal and therefore never experience these symptoms. Of course, it also seems that withdrawal affects everyone differently, and it may be that some people are truly entirely normal after the published 2-9 days that many articles cite. People who experience these difficulties quitting caffeine may be those who are particularly sensitive to it, or perhaps people who have some level of pre-existing anxiety.
It is somewhat better known that antidepressants, such as selective serotonin reuptake inhibitors (SSRIs) can have a syndrome of symptoms after discontinuation, as discussed here. Since caffeine is thought to also have effects on neurotransmitters like dopamine, it is perhaps not surprising that quitting caffeine could have a similar constellation of symptoms. This article notes some patients with long-lasting symptoms from discontinuing SSRI drugs, including development of anxiety from discontinuing the drug.
It should be noted that PAWS is somewhat controversial (see links on this page), since the symptoms are difficult to measure. Some do not acknowledge its existence, whereas others believe this is just a part of withdrawal itself, which should be measured in months rather than days / weeks.
The linked articles here note that PAWS can last months to a year or more, which is remarkably similar to a number of the stories we have collected from individuals feeling fully recovered only after 6-24 months!
American Addiction Centers
This is another article from American Addiction Centers. It discusses PAWS and some of the drugs that have been associated with it. Although caffeine specifically is not listed, stimulants in general are mentioned.
Detoxing after Detox: The Perils of Post-Acute Withdrawal
"It can take four weeks to up to six months for the brain to naturally manufacture enough endorphins and dopamine to replenish its inventory of these vital brain chemicals."