Proctalgia fugax, as its name suggests, is a fleeting pain in the anal region. Typically tucked away in the small print in specialist texts with other pelvic pain syndromes, such as prostatodynia, levator syndrome and coccygodynia, proctalgia fugax is a benign condition variously described as a transient, self-limiting pain in the perineum, anus or rectum. The pain is experienced irregularly either during the day or at night, wakening the sufferer from sleep. It does not appear to be related to defecation in most people. It lasts anywhere from a few minutes to 1 h , yet for all its fleeting nature it comes in for regular attention in the medical literature. Why should this be so? Is it because it affects far more of us than care to admit it? It seems to occur in 14% of healthy adults , but it may be more prevalent. Thompson suggested it was more common in patients attending a gastrointestinal clinic. In this group, proctalgia fugax was not associated with irritable bowel syndrome, and the majority did not seek medical advice . It is often described as affecting young males and can occur spontaneously in middle age . The pattern in patients with other gastrointestinal disorders differs: in this group, 51% of females are affected compared with 12% of males .
The aetiology of proctalgia fugax remains unclear. On the basis of patients experiencing perianal pain with sigmoid colonic contractions, Harvey suggested that proctalgia fugax was an unusual variant of irritable bowel syndrome . Spasm of the skeletal pelvic floor muscles is another possible aetiology; proctalgia fugax, levator ani spasm syndrome, coccygodynia and pyriformis syndrome could all be considered as pelvic floor myalgias. These ‘tension’ myalgias appear to be associated with poor posture, abdominal muscle weakness, and pelvic muscle attachment tenderness . Rao and Hatfield described a paroxysmal anal hyperkinesis as a characteristic feature of proctalgia fugax. They measured standard anorectal physiology, prolonged colonic manometry at six colonic sites, and myoelectrical activity in the anus in a paraplegic patient with a 10-year history of proctalgia fugax. There were 27 reported episodes of pain; 23 (85%) of these were associated with bursts of high-amplitude, high-frequency anal myoelectrical activity. The anorectal manometry showed normal internal sphincter tone and recto-anal inhibitory reflex but an inability to squeeze. Compliance tests showed rectal sensation was absent, and 3 cycles/min phasic contraction of the rectum was not associated with symptoms of proctalgia fugax. Rao and Hatfield argued that the temporal relationship between the symptoms and anal myoelectrical activity suggested a causal link between the increased anal myoelectrical activity and proctalgia fugax . Serendipitously, 2/18 patients in a study by Eckardt et al. experienced proctalgia fugax while undergoing anorectal manometry. Initially studying 18 patients experiencing sporadic proctalgia fugax with age- and sex-matched controls, Eckardt et al. showed that affected people had a slightly higher resting anal pressure, but there was no difference in squeeze pressure, sphincter relaxation, rectal compliance, or internal or external sphincter thickness. When the affected people had symptoms while being studied, a rise in anal resting tone and increased slow-wave amplitude was noted .
Although Eckardt et al. noted no abnormality of the internal anal sphincter, a rare internal anal sphincter myopathy has been described that causes proctalgia fugax and constipation [8–10]. Imaging of the sphincter complex shows marked hypertrophy of the internal sphincter [8,9], and histology shows vacuolar changes with polyglucosan inclusion bodies [8,11]. Treatment of this condition has been attempted with internal anal strip myectomy and topical nitrates .
If the primary aetiology is anal spasm, then treatments that produce relaxation of the internal anal sphincter might be beneficial, particularly now that chronic anal fissures have been shown to heal with the use of topical nitrates . Nearly all medical methods of inducing sphincter relaxation have been described for the treatment of proctalgia fugax, mostly in case report form. Water at 40°C has been shown to reduce resting anal canal pressure , so a warm bath may be a suitable treatment. Nevertheless, salbutamol inhalation , oral clonidine , topical nitrates  and calcium channel blockers  have all been described. A case report describing the use of botulinum A toxin infiltrated into the anal sphincter to successfully treat proctalgia fugax appears in the current issue of this journal . Whether the symptomatic relief is due to the effect of botulinum A toxin on the internal anal sphincter or on the skeletal pelvic floor muscles is debatable, but it is interesting to note that botulinum A toxin has also been used successfully in the relief of chronic prostatic pain. In this study, in addition to urethral symptoms, all patients experienced chronic pelvic floor tenderness and disordered pelvic floor control. Transurethral perisphincteric injection of botulinum A toxin produced pelvic floor muscle weakening and relief of pain .
What next? For the most part, after a detailed history, simple reassurance and a warm bath will suffice for most sufferers. For persistent symptoms, there are a variety of easily administered treatments now available. As for a randomized controlled trial, we shall see.
1. Rao SS, Hatfield RA. Paroxysmal anal hyperkinesis: a characteristic feature of proctalgia
fugax. Gut 1996; 39: 609–612.
2. Thompson WG. Proctalgia
fugax. Dig Dis Sci 1981; 26: 1121–1124.
3. Thompson WG. Proctalgia
fugax in patients with the irritable bowel, peptic ulcer, or inflammatory bowel disease. Am J Gastroenterol 1984; 79: 450–452.
4. Heppell J. Surgery of the Colon and Rectum
. London: Churchill Livingstone; 1997.
5. Harvey RF. Colonic motility in proctalgia
fugax. Lancet 1979; ii: 713–714.
6. Sinaki M, Merritt JL, Stillwell GK. Tension myalgia of the pelvic floor. Mayo Clin Proc 1977; 52: 717–722.
7. Eckardt VF, Dodt O, Kanzler G, Bernhard G. Anorectal function and morphology in patients with sporadic proctalgia
fugax. Dis Colon Rectum 1996; 39: 755–762.
8. Kamm MA, Hoyle CH, Burleigh DE, Law PJ, Swash M, Martin JE. et al
. Hereditary internal anal sphincter myopathy causing proctalgia
fugax and constipation. A newly identified condition. Gastroenterology 1991; 100: 805–810.
9. Guy RJ, Kamm MA, Martin JE. Internal anal sphincter myopathy causing proctalgia
fugax and constipation: further clinical and radiological characterization in a patient. Eur J Gastroenterol Hepatol 1997; 9: 221–224.
10. Celik AF, Katsinelos P, Read NW, Khan MI, Donnelly TC. Hereditary proctalgia
fugax and constipation: report of a second family. Gut 1995; 36: 581–584.
11. Martin JE, Swash M, Kamm MA, Mather K, Cox EL, Gray A. Myopathy of internal anal sphincter with polyglucosan inclusions. J Pathol 1990; 161: 221–226.
12. Lund JN, Scholefield JH. A randomised, prospective, double-blind, placebo-controlled trial of glyceryl trinitrate ointment in treatment of anal fissure. Lancet
:11–14 [published erratum appears in Lancet
13. Dodi G, Bogoni F, Infantino A, Pianon P, Mortellaro LM, Lise M. Hot or cold in anal pain? A study of the changes in internal anal sphincter pressure profiles. Dis Colon Rectum 1986; 29: 248–251.
14. Eckardt VF, Dodt O, Kanzler G, Bernhard G. Treatment of proctalgia
fugax with salbutamol inhalation. Am J Gastroenterol 1996; 91: 686–689.
15. Swain R. Oral clonidine for proctalgia
fugax. Gut 1987; 28: 1039–1040.
16. Lowenstein B, Cataldo PA. Treatment of proctalgia
fugax with topical nitroglycerin: report of a case. Dis Colon Rectum 1998; 41: 667–668.
17. Boquet J, Moore N, Lhuintre JP, Boismare F. Diltiazem for proctalgia
fugax. Lancet 1986; i: 1493.1493.
18. Katsinelos P, Kalomenopoulou M, Christodoulou K, Katsiba D, Tsolkas P, Pilpilidis I. et al
. Treatment of proctalgia
fugax with botulinum A toxin. Eur J Gastroenterol Hepatol 2001; 13: 1371–1373.
19. Zermann D, Ishigooka M, Schubert J, Schmidt RA. Perisphincteric injection of botulinum toxin type A. A treatment option for patients with chronic prostatic pain? Eur Urol 2000; 38: 393–399.