Yun Tae Hwang and Amy Kang
Med J Aust 2015; 203 (11): 470-471. || doi: 10.5694/mja15.01022
Published online: 14 December 2015

A little-known condition — and there is much work to be done

Mondayitis is a widely known and discussed condition in popular culture. Searching for “Mondayitis” on PubMed, however, will not return any positive results (as of Sunday 6 September 2015). We hope to address this gap in knowledge by proposing a number of possible hypotheses as to its cause, and so assist a keen researcher in directing his or her energies in the most fruitful direction for further exploration.


In the absence of a formal medical definition, one must be forgiven for resorting to “Doctor Google” for the popularly accepted meaning. It leads us to a number of definitions all of which emphasise that the symptoms, consisting of apathy and lethargy, are seen on Monday. We believe that this definition requires broadening as it unjustly excludes sufferers who do not work a regular Monday to Friday working week. Hence, we would like to propose a more generalised definition: a systemic illness with a non-specific constellation of symptoms including fatigue, lethargy or asthenia, dysthymia, irritability, light-headedness, photophobia, dry mouth, myalgia, and headache in the absence of another focal or systemic illness. These symptoms commonly manifest as an overwhelming desire to skip work or, if sufficiently mild to allow attendance at work, in a dishevelled appearance and feeling poorly. Symptoms typically occur on the first working day after a period of time off work, which may be as short as 2 days (“the weekend”) or longer (“the long weekend” or “a holiday”).


While there are no studies examining this topic, there would be a general agreement with Urban Dictionary’s assertion that “this feeling [of general distress] is usually enhanced after a large weekend”.1 While exploring the popular definition and threshold of “a large weekend” is beyond the scope of this article, we believe that it would not be unreasonable to assert that it involves a disruption to the usual sleep pattern, consumption of more food and beverages (alcoholic or otherwise) than usual and partaking in extra-occupational and extra-familial social engagements. Based on the above assumptions, we propose a number of possible pathophysiological processes causing Mondayitis.

1 Direct effect of alcohol

Mondayitis could be a version of hangover, a well recognised consequence of alcohol consumption. This may relate to toxic metabolite (mostly acetaldehyde) accumulation, hormonal changes, or dehydration and electrolyte imbalance from alcohol-induced diuresis. This topic is expounded in more detail in Penning and colleagues’ excellent review.2

2 Metabolic derangement, including accumulation of toxic metabolites

Penning’s review also covers the effects of metabolic derangement, particularly acidosis, in the setting of alcohol consumption resulting in hangover-like symptoms.2 In addition, many food items consumed over a “long weekend”, particularly those that are sweet, salty or fatty, may also have a role in creating and sustaining the metabolic derangement and causing the detrimental symptoms of Mondayitis.

3 Transient systemic inflammation

The symptoms of Mondayitis are also consistent with excess cytokine production and a generalised pro-inflammatory state. This state could be triggered, for example, by a viral infection acquired during social engagements in the periods leading up to Monday. Further epidemiological studies are needed to confirm this hypothesis, particularly since the causative virus may not yet have been identified.

4 Reduced sleep and the jet lag effect

Disruption to normal circadian rhythm is known to cause fatigue, reduced concentration, headache and malaise.3 This effect, when associated with the change in time zone after a long-haul flight, is known as jet lag and is widely accepted by the medical and the general community. It is not impossible that alterations to the normal sleep pattern imposed by extra socialisation and “having fun” during the “large weekend” disrupt the normal circadian rhythm, resulting in the same clinical picture as jet lag. If this was indeed the case, we believe that the term “Mondayitis” should be reserved exclusively for the constellation of such symptoms that occur without changing time zones by flying on a jet plane.

5 Withdrawal from an environmental agent

The symptoms of Mondayitis typically resolve by the afternoon of the first working day. This may be because the symptoms are due to substance withdrawal, occurring over 2–3 days, from an environmental agent only found at the workplace, or perhaps even the actual work itself. Admittedly, this seems unlikely and some readers may find this suggestion incredulous and even upsetting. But currently, there is nothing to preclude this possibility and only further research will exclude this hypothesis.


There are many possible causes of Mondayitis. Our suspicion is that Mondayitis has multiple contributing pathophysiological processes, with the exact manifestation determined by the genetic variations in each individual. What is clear, however, is that we know very little about this condition and that there is much work to be done. While Mondayitis may not be a life-threatening disorder, it is a common disease responsible for a significant amount of misery and, as professionals dedicated to alleviating human suffering, we cannot, and must not, continue to neglect this condition.

  • Yun Tae Hwang1
  • Amy Kang2

  • 1 The Canberra Hospital, Canberra, ACT
  • 2 Royal Prince Alfred Hospital, Sydney, NSW


Competing interests:

Both authors have suffered from bouts of Mondayitis on occasions when they were younger.

  • 1. Urban Dictionary [internet]. Mondayitis, updated 18 Nov 2007. San Francisco, Calif: Urban Dictionary LLC. (accessed Sep 2015).
  • 2. Penning R, van Nuland M, Fliervoet LAL, et al. The pathology of alcohol hangover. Current Drug Abuse Rev 2010; 3: 68-75.
  • 3. Leatherwood WE, Dargoo JL. Effect of airline travel on performance: a review of the literature. Br J Sports Med 2013; 47: 561-567.


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access_time 09:03, 15 December 2015
Christina Crawford

Dear Authors
Fantastic article, I think this should come to our Christmas Journal Club for reviewing and although our sample population (5+ Pharmacists) will be small, we will be suitably qualified to observe and record the outcome. However, unsure if literature will support further additions to medical terminology to include Thursdayitis.
Our CPD Record will not withstand this level of Journal Article Review and "hands on/observational reporting" more often than once a year.
What you failed to mention was the chronicity of the condition, could it be considered Acute on Chronic, particularly through December and January in many parts of the world. My own observational studies have led me to noticing the propensity for this condition to return at regular intervals. Often coinciding with annual events amongst friends and family. This condition seems self-limiting and procreation/parenting seems to result in cognitive behaviour therapy changes for most individuals.
With that said, Merry Christmas to One and All.
Moderation is the key to a safe and happy festive season.
Enjoy! Mondayitis, comes but once a week, for about 10 years. Episodically returning, subject to environmental conditions and individual risk factors. More study may be warranted, but funding may be difficult to obtain, especially if job loss is the outcome of an individuals' Mondayitis.

Competing Interests: No relevant disclosures

Mrs Christina Crawford
Community Pharmacy in NZ

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