Tiamulin, a semi-synthetic derivative of the diterpenoid antibiotic truncated pleuromutilin, has been found to be efficacious in the investigation of mycoplasma-primarily induced neck inflammation [1]. Tiamulin is Gram Active against positive bacteria (Staphylococcus, Streptococcus, Clostridium, Mysterella), spirochetes (Brachyspira porcine diarrhea, Brachyspira asexual, Brachyspira pilosa, and Brachyspira intermedius), and mycoplasma strains (Mycoplasma gallisepticum, Mycoplasma synoviae, M. meleagridis, and M. iowae) [1]. However, tiamulin has reduced activity against Gram-negative bacteria (Pasteurella, Klebsiella, Haemophilus, Clostridium, Campylobacter, Bacteroidetes) [1]. In order to allow peptidase and subsequent protein synthesis, tRNA must be properly positioned for CCA termination of the tRNA, which is hindered by titimulin's binding to rRNA in the ribosomal peptidyltransferase groove [1].

Treatment of poultry-destroying spirocheteosis in breeders and eggs with tiamulin (25 mg/kg for 5 days) proved to be highly successful in tests using fake infections with Bacillus trichocystis and Bacillus intermedius [1].

Absorption, Distribution and Excretion
This product is readily absorbed through the intestines and is detectable in the blood within 30 minutes of administration. Tiamulin is well absorbed orally in pigs. Approximately 85% of the dose is absorbed after a single oral administration, with peak plasma concentrations occurring between 2 and 4 hours. Tiamulin is evenly distributed, with the highest concentrations observed in the lungs. In pigs (2 pigs per sex per group), after 10 consecutive days of oral administration of 5 mg (14)C-tiamulin base/kg body weight/day, approximately 35% of the dose was excreted in the urine and 65% in the feces. At 10 days post-administration, the total residual concentrations in the liver, kidneys, muscle, and fat were 21,880, 600, 720, and 720 μg Equivalents/kg, respectively; at 25 days post-administration, they were 480, 220, 430, and 910 μg Equivalents/kg, respectively.

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Metabolisms/Metabolites
After oral administration of 10 mg (3) H-thiamine hydrofumarate/kg body weight/day for 5 consecutive days, more than 15 metabolites were detected in tissue extracts in laying hens, broilers, and turkeys (6 animals per group), but most residues consisted of 4 metabolites. No single metabolite accounted for more than 30% of the total residues in poultry tissues.
In porcine livers after oral administration of tiamulin, the percentages of metabolites that could be hydrolyzed to 8-α-hydroxyimidazoline (i.e., the labeled residues) at 4, 24, and 96 hours after administration were 3.5%, 3.6%, and 5.7% of the total residues, respectively.
In pigs (4 pigs per sex per group) that were allowed free access to a diet containing 39 mg/kg tiamulin for 10 consecutive days, the average concentrations of the metabolite that could be hydrolyzed to 8-α-hydroxyimidazoline in the liver were 447 and 247 μg equivalents/kg at 2 hours and 12 hours after administration, respectively, as determined by gas chromatography-electrochemical detection. In an 18-day animal experiment, the average concentrations of 8-α-hydroxytemoline in the liver were 184, 256, 214, and 175 μg/kg equivalents at 12, 16, 20, and 24 hours after administration, respectively.
In pigs orally administered (3)H-temoline, the residual amount of 6-desmethyltemoline in bile and urine samples was less than 1%, and its antibacterial activity was 67% of that of temoline, as determined by agar diffusion. The antibacterial activity of four other metabolites ranged from 0.7% to 3.3% relative to temoline, while the relative activity of all other metabolites was less than 0.3%. Temoline can be metabolized into more than 20 metabolites, some of which have antibacterial activity. Approximately 30% of these metabolites are excreted in urine, and the remainder in feces.

Toxicity Summary
Identification and Uses: Adding tiamulin to drinking water for five consecutive days is effective in treating swine dysentery caused by Treponema pallidum (formerly known as Treponema sei or Treponema pyrenoidosa) and swine pneumonia caused by Actinobacillus pleuropneumoniae. As a feed additive, it can be used to promote weight gain in pigs. Human Exposure and Toxicity: Topical application of a 0.05% tiamulin formulation did not cause skin irritation or sensitization. Another study was conducted in six healthy male volunteers. Three volunteers received five oral doses, escalating from 0.125 mg/kg body weight to 7.2 mg/kg body weight, with each dose administered 72 hours apart. The remaining volunteers received a single oral dose ranging from 8.2 to 10.7 mg/kg body weight. No drug-related changes were observed in blood pressure, serum chemistry, or electrocardiogram. Animal Studies: Overdose of tiamulin caused transient salivation, vomiting, and significant sedation in pigs. In a subchronic study, rats were fed a diet containing 0.5 or 30 mg/kg body weight/day of tiamulin for 26 consecutive weeks. Other rats received 180 mg/kg body weight/day of tiamulin for 10 consecutive weeks, followed by 270 mg/kg body weight/day of tiamulin for 16 consecutive weeks; one group of rats underwent necropsy at the end of treatment, while the remaining rats continued to be fed an untreated control diet for 4 or 8 weeks. The 180 mg/kg body weight group showed increased serum cholesterol and water intake. When the dose was increased to 270 mg/kg body weight/day, elevated levels of serum alkaline phosphatase, alanine phosphatase, alanine aminotransferase, and aspartate aminotransferase were observed. Abdominal distension, thicker feces, and increased urine specific gravity were also observed. Both absolute and relative liver weights increased in both male and female dogs, and histopathological examination showed hepatic steatosis. In a chronic study, dogs were given oral tiamulin at doses of 0, 3, 10, or 30 mg/kg body weight/day for 54 weeks. In the 10 and 30 mg/kg body weight/day dosing groups, occasional vomiting, decreased serum potassium concentration, and QT interval prolongation on electrocardiogram were observed. Serum lactate dehydrogenase (LDH) was significantly elevated; however, no elevation of the cardiac-related isoenzyme LDH1 was observed. Rats were fed diets containing different concentrations of tiamulin at daily intakes of 0, 2, 8, or 32 mg/kg body weight for 30 months. The results showed no significant dose-related correlation in the incidence of any type of tumor. In another study, mice were fed diets containing the equivalent of 0, 1, 6, or 48 mg/kg body weight/day of tiamulin for up to 123 weeks. The results showed no significant dose-related correlation in the incidence of any type of tumor. Pregnant female rats were orally administered tiamulin at doses of 0, 30, 100, or 300 mg/kg body weight/day daily from day 6 to day 15 of gestation. Mild maternal toxicity was observed at the 300 mg/kg body weight/day dose. At this dose level, the average fetal weight decreased and the incidence of skeletal retardation increased. No evidence of teratogenicity was found. Pregnant female rabbits were administered oral doses of 0, 30, 55, or 100 mg/kg body weight/day daily from day 6 to day 18 of gestation. Doses of 55 mg/kg body weight/day and above resulted in mortality in some does and reduced weight gain. At doses of 55 mg/kg body weight/day and above, both litter size and fetal weight decreased. No teratogenicity was found at any dose level. Several reproductive studies were conducted in pigs. One group of sows was fed a diet containing 200 mg/kg feed from day 84 to day 92 of gestation; another group of sows was fed a diet containing 16 mg/kg body weight/day starting 2 days after mating for 6 weeks; and several other groups of sows had 8.8 mg/kg body weight/day of tiamulin added to their drinking water at different stages of gestation, and in some cases even until weaning. It had no adverse effects on sow health, pregnancy, farrowing, placental size, piglet growth and survival, estrous cycle, or subsequent reproductive performance. Feeding boars a dose of 16 mg/kg body weight/day for 14 days did not affect their health, libido, or semen quality. Tiamulin did not induce gene mutations in Salmonella Typhimurium strains TA98, TA100, TA1535, TA1537, or TA1538. In vitro gene mutation assays at the HPRT locus in V79 Chinese hamster cells were also negative. In the in vivo micronucleus assay in mice, tiamulin had no effect on the frequency of micronuclei in polychromatic erythrocytes.

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Interactions
The toxicological interaction characteristics between monensin and tiamulin were investigated in mice.
In a Phase I clinical trial, a three-day oral repeated-dose toxicity comparison study was conducted, examining the effects of monensin and tiamulin (monensin doses of 10, 30, and 50 mg/kg body weight, and tiamulin doses of 40, 120, and 200 mg/kg body weight). In a Phase II clinical trial, the two compounds were administered concurrently to investigate their toxicity interactions (monensin doses of 10 mg/kg and 40 mg/kg body weight). Results showed that monensin was toxic to rats at doses of 30 and 50 mg/kg. Tiamulin was well tolerated at a dose of 200 mg/kg. Following combined administration, toxic symptoms (including death in female rats) were observed. Monensin at a dose of 50 mg/kg caused dose-dependent cardiotoxicity and vacuolar degeneration of skeletal muscle. Both compounds were hepatotoxic at high doses. Concomitant administration of both compounds had a slight effect on the liver (females only), leading to myocardial edema and vacuolar degeneration of skeletal muscle. Changes in skeletal muscle were more pronounced than after administration of monensin alone at 50 mg/kg. This study aimed to investigate the effects of monensin and tiamulin, as well as the combined administration of both compounds, on rat microsomal enzymes. In the first phase of the experiment, the effects of monensin and tiamulin were investigated separately (monensin doses of 10, 30, and 50 mg/kg body weight, and tiamulin doses of 40, 120, and 200 mg/kg body weight); in the second phase, both compounds were administered simultaneously (monensin dose of 10 mg/kg body weight and tiamulin dose of 40 mg/kg body weight). Monensin alone had no significant effect on hepatic microsomal enzymes. In a few cases, slight inhibition of some enzyme activities was observed. Tiamulin induced dose-dependent liver enzyme induction. Low doses (10 and 40 mg/kg, respectively) of monensin and tiamulin combined significantly increased the activity of P450-related enzymes. This enzyme induction was more pronounced in females than in males. The results indicated that concomitant use of tiamulin may affect the biotransformation of monensin, potentially increasing the amount of the active metabolite of this ionophoretic antibiotic. Tiamulin is a commonly used antibiotic in veterinary medicine. Studies have shown that this drug can have clinically significant interactions with other concomitantly used compounds. This study investigated the effect of tiamulin on CYP3A4 activity using the NIH/3T3 cell line stably expressing human cytochrome P450 (EC 1.14.14.1) cDNA (CYP3A4). Compared to vector-transfected cells, cells expressing CYP3A4 showed enhanced 6β-hydroxylation activity of testosterone, but this activity decreased after incubation with 1 μM tiamulin, and completely decreased to background levels after incubation with 2, 5, and 10 μM tiamulin. The effect of tiamulin on CYP3A4-mediated mutagenicity of aflatoxin B1 was investigated by combining this CYP3A4-expressing cell line with a shuttle vector containing the bacterial lacZ' gene. In cells expressing CYP3A4, the mutation frequency of aflatoxin B1 was completely suppressed by thiamethoxam, but no effect was observed on the mutation frequency of the direct mutagen ethyl mesylate. Western blot analysis of homogenates from CYP3A4-expressing cell lines showed that the CYP3A4 protein was stable after incubation with tiamulin, supporting the hypothesis that tiamulin exerts its inhibitory effect through cytochrome binding. In poultry, tiamulin interferes with the metabolism of monensin and salinomycin; co-administration of these two drugs can lead to toxicity. For more complete data on tiamulin interactions (10 items total), please visit the HSDB record page.

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Non-human toxicity values
Oral LD50 in rats: 2230 mg/kg
Subcutaneous LD50 in rats: 4380 mg/kg
Intravenous LD50 in rats: 20 mg/kg
Oral LD50 in mice: 710 mg/kg
For more complete non-human toxicity data for tiamulin, please visit the HSDB record page. (Total 15 cases), please visit the HSDB record page.

[1]. Islam KM, et al. The activity and compatibility of the antibiotic tiamulin with other drugs in poultry medicine--A review. Poult Sci. 2009 Nov;88(11):2353-9.

Tiamulin is a C3-cyclic compound, a derivative of truncated pleurotin, wherein the glycolic acid group is replaced by a 2-{[2-(diethylamino)ethyl]thio}acetic acid group. Tiamulin is an antimicrobial drug used in veterinary medicine to treat swine dysentery caused by Serpula hyodysenteriae (usually in its fumarate form). It is a C3-cyclic compound, carboxylic acid ester, cyclic ketone, tertiary amine compound, secondary alcohol, organosulfur compound, tetracyclic diterpenoid, and semi-synthetic derivative. It is functionally related to truncated pleurotin. Tiamulin is a truncated pleurotin antibiotic used in veterinary medicine to treat diseases in pigs and poultry. See also: Tiamulin fumarate (salt form). Chlorotetracycline; Tiamulin (ingredient).

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Mechanism of Action
In cells expressing CYP3A4, tiamulin completely inhibited the mutation frequency of aflatoxin B1, but had no effect on the mutation frequency of the direct mutagen ethyl mesylate. Western blot analysis of homogenates of CYP3A4-expressing cell lines showed that CYP3A4 protein was stable after tiamulin incubation, supporting the hypothesis that tiamulin exerts its inhibitory effect through binding to cytochromes.
Tiamulin is a semi-synthetic diterpenoid antibiotic commonly used in farm animals. This drug has been shown to have clinically significant interactions with other compounds, which can even be fatal. Studies have shown that this is due to tiamulin selectively inhibiting the oxidative metabolism of the drug by forming a cytochrome P-450 metabolic intermediate complex. In this study, rats were orally administered two different doses of tiamulin for six consecutive days: 40 and 226 mg/kg body weight. As a control, another group of rats were orally administered 300 mg/kg body weight of triacetyl-Olimycin (TAO), a dose equivalent to the 226 mg/kg tiamulin group. Subsequently, microsomal P-450 content, P-450 enzyme activity, metabolic intermediate complex spectra, and P-450 apolipoprotein concentration were measured. Furthermore, the effects of different tiamulin and substrate concentrations on the activities of various P-450 enzymes in control microsomes were investigated. In tiamulin-treated rats, dose-dependent complex formation (confirmed by absorption spectroscopy) and increased cytochrome P-450 3A1/2 content were observed (detected by Western blotting). These effects were comparable to those of TAO. Tiamulin induced microsomal P-450 content, testosterone 6β-hydroxylation rate, erythromycin N-demethylation rate, and ethoxyhalonil O-deethylation activity. Other activities were unaffected or decreased. When tiamulin was added to the microsomes of control rats, the 6β-hydroxylation rate of testosterone and the N-demethylation activity of erythromycin were significantly inhibited. This leads to the conclusion that tiamulin is a potent and selective cytochrome P-450 inducer-inhibitor. Although not a macrolide antibiotic, its effect on P-450 is similar to that of TAO and related compounds.

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Therapeutic Use
Antibacterial Agent
Drug (Veterinary): Denagard (tiamulin) added to drinking water for five consecutive days is effective in treating swine dysentery caused by Treponema pallidum (formerly known as Serpulina or Treponema) sensitive to tiamulin, at a daily dose of 3.5 mg tiamulin fumarate per pound of body weight; it can also treat swine pneumonia caused by Actinomyces pleuropneumoniae sensitive to tiamulin, at a daily dose of 10.5 mg tiamulin fumarate per pound of body weight. /US Product Label Includes/
Veterinary Drug: Tiamulin is a diterpenoid veterinary drug widely used for the control of infectious diseases in pigs, including swine dysentery and endemic pneumonia.
Veterinary Drug: In veterinary medicine, tiamulin is used to treat and prevent dysentery, pneumonia, and mycoplasma infections in pigs and poultry.

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Drug Warning
For Animal Use Only - Not for Human Use.
Pigs receiving Denagard (tiamulin) should not be exposed to feed containing polyether ionocarriers (e.g., monensin, lasaloxicillin, nalaxyl, thalimycin, and ceduramycin) as adverse reactions may occur.
The likelihood of adverse reactions to this drug is very low at commonly used doses. In rare cases, skin redness may be observed, primarily on the hind legs and abdomen. It is recommended to discontinue the medication, provide clean drinking water, and flush the affected area or move the affected animal to a clean pen. In poultry, tiamulin interferes with the metabolism of monensin and thalidomide, and toxicity can occur if these two drugs are fed simultaneously. Pigs receiving Denagard (tiamulin) treatment should not be exposed to feed containing polyether ionocarriers (such as monensin, lasaloxicillin, nalaxyl, thalidomide, and ceduramycin) as adverse reactions may occur.

C28H47NO4S

493.7421

493.322

C, 68.11; H, 9.60; N, 2.84; O, 12.96; S, 6.49

55297-95-5

Tiamulin fumarate;55297-96-6

656958

Sticky, translucent yellowish mass

1.1±0.1 g/cm3

563.0±50.0 °C at 760 mmHg

147-148ºC

294.3±30.1 °C

0.0±3.5 mmHg at 25°C

1.541

5.93

1

6

10

34

770

8

S(C([H])([H])C([H])([H])N(C([H])([H])C([H])([H])[H])C([H])([H])C([H])([H])[H])C([H])([H])C(=O)O[C@]1([H])C([H])([H])[C@](C([H])=C([H])[H])(C([H])([H])[H])[C@]([H])([C@]([H])(C([H])([H])[H])[C@]23C([H])([H])C([H])([H])C([C@@]2([H])C1(C([H])([H])[H])C([H])(C([H])([H])[H])C([H])([H])C3([H])[H])=O)O[H]

UURAUHCOJAIIRQ-KWVPEQCVSA-N

InChI=1S/C28H47NO4S/c1-8-26(6)17-22(33-23(31)18-34-16-15-29(9-2)10-3)27(7)19(4)11-13-28(20(5)25(26)32)14-12-21(30)24(27)28/h8,19-20,22,24-25,32H,1,9-18H2,2-7H3/t19-,20+,22-,24+,25+,26-,27-,28+/m1/s1

(3aS,4R,5S,6S,8R,9S,9aR,10R)-2-[[2-(Diethylamino)ethyl]thio]acetic Acid 6-Ethenyldecahydro-5-hydroxy-4,6,9,10-tetramethyl-1-oxo-3a,9-propano-3aH-cyclopentacycloocten-8-yl Ester

SQ 14055; SQ-14055; SQ14055; Tiamulin;

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

DMSO : ~98 mg/mL ( ~198.48 mM )
Water : ~98 mg/mL
Ethanol : ~98 mg/mL

Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples.

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Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline)
*Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution.
Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)
Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil)
Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals).

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Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)]
*Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.
Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline)
Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline)
Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline)
Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline
Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil)
Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)

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Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium)
Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose
Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals).

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Oral Formulation 3: Dissolved in PEG400
Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose
Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose
Oral Formulation 6: Mixing with food powders

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Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.

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 (Please use freshly prepared in vivo formulations for optimal results.)