Hyoscyamine

Source: Wikipedia, the free encyclopedia.

Hyoscyamine
By mouth, Injection
ATC code
Legal status
Legal status
Pharmacokinetic data
Bioavailability50% protein binding
MetabolismLiver
Elimination half-life3–5 hrs.
ExcretionKidney
Identifiers
  • (S)-(1R,3r,5S)-8-methyl-8-azabicyclo[3.2.1]octan-3-yl 3-hydroxy-2-phenylpropanoate
JSmol)
  • CN3[C@H]1CC[C@@H]3C[C@@H](C1)OC(=O)[C@H](CO)c2ccccc2
  • InChI=1S/C17H23NO3/c1-18-13-7-8-14(18)10-15(9-13)21-17(20)16(11-19)12-5-3-2-4-6-12/h2-6,13-16,19H,7-11H2,1H3/t13-,14+,15+,16-/m1/s1 checkY
  • Key:RKUNBYITZUJHSG-FXUDXRNXSA-N checkY
 ☒NcheckY (what is this?)  (verify)

Hyoscyamine (also known as daturine or duboisine) is a naturally occurring

levorotary isomer of atropine (third of the three major nightshade alkaloids) and thus sometimes known as levo-atropine.[1]

In 2021, it was the 272nd most commonly prescribed medication in the United States, with more than 900,000 prescriptions.[2][3]

Medical uses

Hyoscyamine is used to provide symptomatic relief of spasms caused by various lower abdominal and bladder disorders including

peptic ulcers, irritable bowel syndrome, diverticulitis, pancreatitis, colic, and interstitial cystitis.[4][5][6] It has also been used to relieve some heart problems, control some of the symptoms of Parkinson's disease, as well as for control of abnormal respiratory symptoms and "hyper-mucus secretions" in patients with lung disease.[7]

Brown glass medicine bottle with label reading, "CLAP MIXTURE," a list of ingredients, "CAUTION -- It is dangerous to exceed the stated dose / DOSES / 1/2 fluid ounce three times a day, in water / SHAKE THE BOTTLE"
The ingredients of this Clap Mixture are sodium citrate, sodium bicarbonate, liquid extract of hyoscyamine and cloroform dissolved in water.

It is also useful in pain control for neuropathic pain, chronic pain and palliative care — "comfort care" — for those with intractable pain from treatment resistant, untreatable, and incurable diseases. When combined with opioids it increases the level of analgesia (pain relief) obtained.

hyoscine and other members of the anticholinergic drug group like cyclobenzaprine, trihexyphenidyl, and orphenadrine are also used for this purpose.[9] When hyoscyamine is used along with opioids or other anti-peristaltic agents, measures to prevent constipation are especially important given the risk of paralytic ileus.[10]

Adverse effects

Side effects include dry mouth and throat, increased appetite leading to weight gain, eye pain, blurred vision, restlessness, dizziness,

hyoscine, as well as dicycloverine, orphenadrine, cyclobenzaprine, trihexyphenidyl, and ethanolamine antihistamines like phenyltoloxamine.[11][12]

Pharmacology

Hyoscyamine is an

hyoscine (known in the United States as Scopolamine) has 92 per cent of the antimuscarinic potency of atropine.[14]

Biosynthesis in plants

Biochemistry of tropane class compounds. Hyoscyamine and scopolamine are present and labeled in the diagram.

Hyoscyamine can be extracted from plants of the family

plant biosynthesis of hyoscine, it is produced via the same metabolic pathway.[15]

The biosynthesis of hyoscine begins with the decarboxylation of L-ornithine to putrescine by ornithine decarboxylase (EC 4.1.1.17). Putrescine is methylated to N-methylputrescine by putrescine N-methyltransferase (EC 2.1.1.53).[15]

A putrescine oxidase (EC 1.4.3.10) that specifically recognizes methylated putrescine catalyzes the deamination of this compound to 4-methylaminobutanal which then undergoes a spontaneous ring formation to N-methylpyrrolium cation. In the next step, the pyrrolium cation condenses with acetoacetic acid yielding hygrine. No enzymatic activity could be demonstrated that catalyzes this reaction. Hygrine further rearranges to tropinone.[15]

Subsequently, tropinone reductase I (EC 1.1.1.206) converts tropinone to tropine which condenses with phenylalanine-derived phenyllactate to littorine. A cytochrome P450 classified as Cyp80F1[16] oxidizes and rearranges littorine to hyoscyamine aldehyde.

Bush medicine basis

A

Invasion of Normandy. Later, it was found that the same substance could be used in the production of scopolamine and hyoscyamine, which are used in eye surgery, and a multi-million dollar industry was built in Queensland based on this substance.[17]

Society and culture

Brand names

Brand names for hyoscyamine include Symax, HyoMax, Anaspaz, Egazil, Buwecon, Cystospaz, Levsin, Levbid, Levsinex, Donnamar, NuLev, Spacol T/S, and Neoquess.[18]

References

  1. PMID 30545219
    .
  2. ^ "The Top 300 of 2021". ClinCalc. Archived from the original on 15 January 2024. Retrieved 14 January 2024.
  3. ^ "Hyoscyamine - Drug Usage Statistics". ClinCalc. Retrieved 14 January 2024.
  4. National Library of Medicine
    .
  5. ^ a b "Hyoscyamine Uses, Side Effects & Warnings". Drugs.com. Archived from the original on 20 August 2022. Retrieved 20 August 2022.
  6. ^ "Bladder Control Medicines | NIDDK". National Institute of Diabetes and Digestive and Kidney Diseases. Archived from the original on 20 August 2022. Retrieved 20 August 2022.
  7. ^ "Hyoscyamine: MedlinePlus Drug Information". medlineplus.gov. Archived from the original on 20 August 2022. Retrieved 20 August 2022.
  8. S2CID 12602416
    .
  9. .
  10. .
  11. PMID 29489152. Archived from the original
    on 20 August 2022.
  12. ^ "Hyoscyamine Sulfate Sublingual Tablets, 0.125 mgRx Only". www.dailymed.nlm.nih.gov. Archived from the original on 20 August 2022. Retrieved 20 August 2022.
  13. ^ Edwards Pharmaceuticals, Inc., Belcher Pharmaceuticals, Inc. (May 2010). "DailyMed". U.S. National Library of Medicine. Retrieved 13 January 2013.
  14. ^ . Retrieved 11 January 2014.
  15. ^ .
  16. .
  17. ^ "Visitors to Art of Healing exhibition told how Australian Indigenous bush medicine was given to every allied soldier landing at Normandy on D-Day". King's College London. 7 June 2019. Retrieved 2 June 2020.
  18. ^ "Hyoscyamine - brand name list from Drugs.com". Drugs.com. Archived from the original on 20 August 2022. Retrieved 20 August 2022.