Skeletal formula
Space-filling model
Clinical data
Trade namesTolectin
Routes of
By mouth
ATC code
Legal status
Legal status
  • AU: S4 (Prescription only)
Pharmacokinetic data
Elimination half-life1-2 hours, next phase up to 5 hours
  • [1-methyl-5-(4-methylbenzoyl)-1H-pyrrol-2-yl]acetic acid
CAS Number
PubChem CID
CompTox Dashboard (EPA)
ECHA InfoCard100.043.164 Edit this at Wikidata
Chemical and physical data
Molar mass257.289 g·mol−1
3D model (JSmol)
  • O=C(c1ccc(n1C)CC(=O)O)c2ccc(cc2)C
  • InChI=1S/C15H15NO3/c1-10-3-5-11(6-4-10)15(19)13-8-7-12(16(13)2)9-14(17)18/h3-8H,9H2,1-2H3,(H,17,18) checkY
 ☒NcheckY (what is this?)  (verify)

Tolmetin (/ˈtɒlmətɪn/) is a nonsteroidal anti-inflammatory drug (NSAID) of the heterocyclic acetic acid derivative class.

Tolmetin was originally approved by the US FDA in 1976. It is available internationally.[1]

It is used primarily to reduce hormones that cause pain, swelling, tenderness, and stiffness in conditions such as osteoarthritis and rheumatoid arthritis, including juvenile rheumatoid arthritis. In the United States it was marketed as Tolectin and comes as a tablet or capsule.

Clinical usage

Tolmetin is applicable in the treatment of rheumatoid arthritis,[2][3] osteoarthrosis,[4][5] pain,[6] and ankylosing spondylitis.[7]

Mechanism of action

Although the mechanism of action of tolmetin is unknown, research involving humans and animals has shown that tolmetin does not achieve anti-inflammatory response by stimulation of the adrenal or pituitary gland, but it has shown tolmetin restrains prostaglandin synthetase in vitro and reduces plasma levels of prostaglandin E, possibly causing the anti-inflammatory response.

When tested in rats, tolmetin prevented experimentally stimulated polyarthritis and reduced inflammation. In patients with rheumatoid arthritis or osteoarthritis tolmetin was as effective as aspirin and indometacin, although the occurrence of mild gastrointestinal adverse effects and tinnitus was lower in patients treated with tolmetin than it was with aspirin-treated patients and the occurrence of adverse effects of the central nervous system was lower with tolmetin than it was with indomethacin.[8]

Side effects

Tolmetin can increase the risk of heart or circulatory conditions such as heart attacks and strokes. It should not be taken shortly before or after coronary artery bypass surgery.[9] Tolmetin can also increase the risk of gastrointestinal conditions such as perforation or bleeding, which can be fatal. Antacids can be taken with tolmetin to relieve stomachaches that often occur.[9] Overdose can result in drowsiness, nausea, epigastric pain, and vomiting.

In October 2020, the U.S. Food and Drug Administration (FDA) required the drug label to be updated for all nonsteroidal anti-inflammatory medications to describe the risk of kidney problems in unborn babies that result from low amniotic fluid.[10][11] They recommend avoiding NSAIDs in pregnant women at 20 weeks or later in pregnancy.[10][11]


  1. ^ "Tolmetin: MedlinePlus Drug Information". Retrieved 2023-10-27.
  2. ^ Cordrey LJ (October 1976). "Tolmetin sodium, a new anti-arthritis drug: double-blind and long-term studies". Journal of the American Geriatrics Society. 24 (10): 440–6. doi:10.1111/j.1532-5415.1976.tb03256.x. PMID 61224. S2CID 26040280.
  3. ^ Cardoe N, Steele CE (1976–1977). "A double-blind crossover comparison of tolmetin sodium and phenylbutazone in the treatment of rheumatoid arthritis". Current Medical Research and Opinion. 4 (10): 688–94. doi:10.1185/03007997609112003. PMID 800970.
  4. ^ Liyanage SP, Steele CE (1977–1978). "Tolmetin in osteoarthrosis of the hip and knee: double-blind crossover trials". Current Medical Research and Opinion. 5 (4): 299–305. doi:10.1185/03007997709110184. PMID 343992.
  5. ^ Davies J, Dixon AS, Steele CE (1980). "Tolmetin sodium and indomethacin in the treatment of osteoarthrosis of the hip: a double-blind crossover study". Current Medical Research and Opinion. 7 (2): 115–20. doi:10.1185/03007998009112037. PMID 7002480.
  6. ^ Stacher G, Bauer P, Ehn I, Schreiber E (June 1979). "Effects of tolmetin, paracetamol, and of two combinations of tolmetin and paracetamol as compared to placebo on experimentally induced pain. A double blind study". International Journal of Clinical Pharmacology and Biopharmacy. 17 (6): 250–5. PMID 381221.
  7. ^ Calin A (July 1983). "Clinical use of tolmetin sodium in patients with ankylosing spondylitis: a review". Journal of Clinical Pharmacology. 23 (7): 301–8. doi:10.1002/j.1552-4604.1983.tb02740.x. PMID 6350376. S2CID 33879936.
  8. ^ "Tolmetin". DrugBank. Retrieved 2007-07-02.
  9. ^ a b "Tolmetin". MedlinePlus. Archived from the original on 2007-06-10. Retrieved 2007-07-02.
  10. ^ a b "FDA Warns that Using a Type of Pain and Fever Medication in Second Half of Pregnancy Could Lead to Complications". U.S. Food and Drug Administration (FDA) (Press release). 15 October 2020. Retrieved 15 October 2020. Public Domain This article incorporates text from this source, which is in the public domain.
  11. ^ a b "NSAIDs may cause rare kidney problems in unborn babies". U.S. Food and Drug Administration. 21 July 2017. Retrieved 15 October 2020. Public Domain This article incorporates text from this source, which is in the public domain.