Absorption, Distribution and Excretion
Oral bioavailability is nearly complete, at approximately 90%, and peak serum concentrations (Cmax) of, on average, 2.50 µg/mL are reached at 0.75 hours (Tmax). The AUC following an orally administered dose of 300mg was found to be approximately 11 µg•hr/mL. Systemic exposure from the administration of vaginal suppository formulations is 40-fold to 50-fold lower than that observed following parenteral administration and the Cmax observed following administration of vaginal cream formulations was 0.1% of that observed following parenteral administration.
Approximately 10% of clindamycin bioactivity is excreted in the urine and 3.6% in the feces, with the remainder excreted as inactive metabolites.
Clindamycin is widely distributed in the body, including into bone, but does not distribute into cerebrospinal fluid. The volume of distribution has been variably estimated between 43-74 L.
The plasma clearance of clindamycin is estimated to be 12.3-17.4 L/h, and is reduced in patients with cirrhosis and altered in those with anemia.
Clindamycin is nearly completely absorbed following oral admin. Peak plasma concn of 2 to 3 ug/mL are attained within 1 hr after the ingestion of 150 mg. The presence of food in stomach does not reduce absorption. The half-life of the antibiotic is about 2.9 hr, and the modest accumulation of drug is thus expected if it is given at 6-hr intervals.
Clindamycin is widely distributed in many fluids and tissues, including bone. Significant concn are not attained in cerebrospinal fluid, even when the meninges are inflamed. Concn sufficient to treat cerebral toxoplasmosis are achievable .. The drug readily crosses the placental barrier. 90% or more of clindamycin is bound to plasma proteins. Clindamycin accumulates in polymorphonuclear leukocytes, alveolar macrophages, and in abscesses.
Half-life ... is lengthened only slightly in patients with markedly impaired renal function ...
Clindamycin is distributed into many body tissues and fluids including saliva, ascites fluid, pleural fluid, synovial fluid, bone, and bile. However, even in the presence of inflamed meninges, only small amounts of the drug diffuse into CSF. The concentration of clindamycin in synovial fluid and bone is reported to be 60-80% of concurrent serum concentrations of the drug; the degree of penetration does not appear to be affected by joint inflammation. Clindamycin readily crosses the placenta, and cord blood concentrations of the drug have been reported to be 46% of concurrent maternal blood concentrations. Clindamycin is distributed into milk.
For more Absorption, Distribution and Excretion (Complete) data for CLINDAMYCIN (24 total), please visit the HSDB record page.

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Metabolism / Metabolites
Clindamycin undergoes hepatic metabolism mediated primarily by CYP3A4 and, to a lesser extent, CYP3A5. Two inactive metabolites have been identified - an oxidative metabolite, clindamycin sulfoxide, and an N-demethylated metabolite, N-desmethylclindamycin.
Clindamycin is partially metabolized to bioactive and inactive metabolites. The major bioactive metabolites are clindamycin sulfoxide and N-demethyl-clindamycin which are excreted in urine, bile, and feces. Within 24 hours, approximately 10% of an oral dose of clindamycin is excreted in urine and 3.6% is excreted in feces as active drug and metabolites; the remainder is excreted as inactive metabolites.
Only about 10% of the clindamycin admin is excreted unaltered in urine, and small quantities are found in feces ... Clindamycin is inactivated by metabolism to N-demethylclindamycin and clindamycin sulfoxide, which are excreted in the urine and bile.
Clindamycin has known human metabolites that include N-desmethyclindamycin and clindamycin sulfoxide.

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Biological Half-Life
The elimination half-life of clindamycin is about 3 hours in adults and 2.5 hours in children. Half-life is increased to approximately 4 hours in the elderly.
The serum half-life of clindamycin is 2-3 hours in adults and children with normal renal function. The serum half-life is increased slightly in patients with markedly reduced renal or hepatic function. In neonates, the serum half-life depends on gestational and chronologic age and body weight. The serum half-life of clindamycin reportedly averages 8.7 and 3.6 hours in premature and full-term neonates, respectively, and about 3 hours in infants 4 weeks to 1 year of age; serum half-life was longer in infants weighing less than 3.5 kg than in heavier infants.
The half-life of ... /clindamycin/ is about 2.9 hr ...
Following intravaginal application of 2% clindamycin cream, the systemic half-life of the drug appears to be about 1.5-2.6 hours. Following intravaginal administration of clindamycin suppositories, the apparent elimination half-life averaged about 11 hours (range: 4-35 hours).

Hepatotoxicity
Clindamycin has been linked to two forms of hepatotoxicity: transient serum aminotransferase elevations usually occurring after several days of high intravenous doses; and, an acute, idiosyncratic liver injury that arises within 1 to 3 weeks of starting therapy and is typically mild and self-limited.
High doses of intravenous clindamycin can be accompanied by elevations in serum ALT levels in the range of 2 to 10 times the upper limit of normal starting after 5 to 15 days of therapy in a manner similar to what occurs with intravenous oxacillin therapy (Case 1). Symptoms, jaundice, and alkaline phosphatase elevations are mild if they occur at all (Case 2), and aminotransferase levels rapidly fall into the normal range (in 1 to 2 weeks) upon stopping clindamycin or switching to lower doses or to oral formulations with which it rarely occurs.
Clindamycin therapy has also been linked to a clinically apparent, idiosyncratic liver injury that arises between 1 to 3 weeks after starting either oral or parenteral therapy (Case 3). The pattern of serum enzyme elevations is typically hepatocellular or mixed, but can be cholestatic. Allergic manifestations such as rash, fever and eosinophilia are typical, but often are not prominent and are not present in all cases. Autoantibodies are generally not present. The acute liver injury may accompany other signs of hypersensitivity such as Stevens Johnson syndrome or other severe skin reactions. The liver injury is usually mild-to-moderate in severity and resolves rapidly with stopping. However, fatal instances have been reported.
Likelihood score: B (highly likely cause of clinically apparent liver injury).

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Effects During Pregnancy and Lactation
◉ Summary of Use during Lactation
Clindamycin has the potential to cause adverse effects on the breastfed infant's gastrointestinal flora. If oral or intravenous clindamycin is required by a nursing mother, it is not a reason to discontinue breastfeeding, but an alternate drug may be preferred. Monitor the infant for possible effects on the gastrointestinal flora, such as diarrhea, candidiasis (thrush, diaper rash) or rarely, blood in the stool indicating possible antibiotic-associated colitis.
Vaginal application is unlikely to cause infant side effects, although about 30% of a vaginal dose is absorbed. Infant side effects are unlikely with topical administration for acne; however, topical application to the breast may increase the risk of diarrhea if it is ingested by the infant. Only water-miscible cream, foam, gel or liquid products should be applied to the breast because ointments may expose the infant to high levels of mineral paraffins via licking.
◉ Effects in Breastfed Infants
Bloody stools in a 5-day-old breastfed infant were possibly caused by concurrent maternal clindamycin 600 mg intravenously every 6 hours and gentamicin 80 mg intravenously every 8 hours. The infant's stools were reported to have normal flora and the stools became guaiac negative 24 hours after discontinuation of breastfeeding. On day 6 of age, the infant resumed breastfeeding after discontinuation of maternal antibiotics with no further difficulties.
◉ Effects on Lactation and Breastmilk
Relevant published information was not found as of the revision date.
◈ What is clindamycin?
Clindamycin is an antibiotic used to treat or prevent bacterial infections. It can be taken by mouth (oral), used on the skin (topical), or given by IV (intravenous or by needle into a vein).Sometimes when people find out they are pregnant, they think about changing how they take their medication, or stopping their medication altogether. However, it is important to talk with your healthcare providers before making any changes to how you take this medication. Your healthcare providers can talk with you about the benefits of treating your condition and the risks of untreated illness during pregnancy.
◈ I take clindamycin. Can it make it harder for me to get pregnant?
It is not known if clindamycin can make it harder to get pregnant.
◈ Does taking clindamycin increase the chance for miscarriage?
Miscarriage is common and can occur in any pregnancy for many different reasons. One study involving 249 women who had a vaginal bacterial infection found that clindamycin treatment reduced the chances of late miscarriage.
◈ Does taking clindamycin increase the chance of birth defects?
Every pregnancy starts out with about a 1 in 33 (3%) chance of having a birth defect. This is called the background chance. It is unlikely that using clindamycin increases the chance of birth defects. Several human studies as well as animal studies have not shown an increased chance of birth defects.When clindamycin is used on the skin (topical use), only small amounts pass through skin and get into the bloodstream. This means a pregnancy would be exposed to only a very small amount of the medicine. Since available information about vaginal and oral clindamycin (both higher absorptions compared to topical use) does not find an increased chance of birth defects, it is also unlikely that using topical clindamycin increases the chance of birth defects.
◈ Does taking clindamycin in pregnancy increase the chance of other pregnancy related problems?
Several studies have not found an increased chance of other pregnancy-related problems such as low birth weight (weighing less than 5 pounds, 8 ounces [2500 grams] at birth). One study involving 249 women who had a vaginal bacterial infection found that clindamycin treatment reduced the chances of preterm delivery (birth before week 37).
◈ Does taking clindamycin in pregnancy affect future behavior or learning for the child?
Studies have not been done to see if clindamycin can cause behavior or learning issues for the child.
◈ Breastfeeding while taking clindamycin:
Clindamycin gets into breastmilk in small amounts when women are given clindamycin orally (by mouth) or intravenously (IV). In those situations, clindamycin might cause some gastrointestinal (GI) effects in a breastfeeding (e.g. nausea, diarrhea, stomach pain, vomiting, diaper rash, thrush, or rarely bloody stools). Topical application (to the skin) has minimal absorption into the body and are unlikely to end up in breast milk in amounts that might cause side effects in a nursing baby. If you notice any symptoms in your child, contact their healthcare provider. Be sure to talk to your healthcare provider about all of your breastfeeding questions.
◈ If a male takes clindamycin, could it affect fertility or increase the chance of birth defects?
Studies have not been done to see if clindamycin could affect male fertility (ability to get partner pregnant) or increase the chance of birth defects above the background risk. In general, exposures that fathers or sperm donors have are unlikely to increase the risks to a pregnancy. For more information, please see the MotherToBaby fact sheet Paternal Exposures at https://mothertobaby.org/fact-sheets/paternal-exposures-pregnancy/.

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Protein Binding
Clindamycin protein binding is concentration-dependent and ranges from 60-94%. It is bound primarily to alpha-1-acid glycoprotein in the serum.

:Ann Clin Microbiol Antimicrob. 2018 Oct 20;17(1):38.

Clindamycin is a semi-synthetic lincosamide antibiotic used in the treatment of a variety of serious infections due to susceptible microorganisms as well as topically for acne vulgaris. It has a relatively narrow spectrum of activity that includes anaerobic bacteria as well as gram-positive cocci and bacilli and gram-negative bacilli. Interestingly, clindamycin appears to carry some activity against protozoans, and has been used off-label in the treatment of toxoplasmosis, malaria, and babesiosis. Clindamycin is derived from, and has largely replaced, [lincomycin], a naturally occurring lincosamide and the eponymous member of this antibiotic class, due to its improved properties over the parent compound. The name lincomycin is derived from Lincoln, Nebraska, where it was first isolated from Streptomyces lincolnensis found in a soil sample.
Clindamycin is a Lincosamide Antibacterial. The physiologic effect of clindamycin is by means of Decreased Sebaceous Gland Activity, and Neuromuscular Blockade.
Clindamycin is a broad spectrum antibiotic used orally, topically and parenterally for bacterial infections due to sensitive organisms. Clindamycin has been linked to rare instances of acute liver injury.
Clindamycin is a semisynthetic broad spectrum antibiotic produced by chemical modification of the parent compound lincomycin. Clindamycin dissociates peptidyl-tRNA from the bacterial ribosome, thereby disrupting bacterial protein synthesis. (NCI04)
An antibacterial agent that is a semisynthetic analog of LINCOMYCIN.
See also: Clindamycin Phosphate (has salt form); Clindamycin Hydrochloride (has salt form); Clindamycin Palmitate Hydrochloride (has salt form) ... View More ...

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Drug Indication
In oral and parenteral formulations, clindamycin is indicated for the treatment of serious infections caused by susceptible anaerobic bacteria, as well as susceptible staphylococci, streptococci, and pneumococci. Used topically, it is indicated for the treatment of acne vulgaris and is available in combination with [benzoyl peroxide] or [tretinoin] for this purpose, or as a triple combination therapy with benzoyl peroxide and [adapalene]. Clindamycin is also indicated as a vaginal cream, suppository, or gel for the treatment of bacterial vaginosis in non-pregnant females. Clindamycin is used for antimicrobial prophylaxis against _Viridans_ group streptococcal infections in susceptible patients undergoing oral, dental, or upper respiratory surgery, and may be used for prophylaxis against bacterial endocarditis in penicillin-allergic patients at high risk of these infections.
FDA Label

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Mechanism of Action
Clindamycin inhibits bacterial protein synthesis by binding to 23S RNA of the 50S subunit of the bacterial ribosome. It impedes both the assembly of the ribosome and the translation process. The molecular mechanism through which this occurs is thought to be due to clindamycin's three-dimensional structure, which closely resembles the 3'-ends of L-Pro-Met-tRNA and deacylated-tRNA during the peptide elongation cycle - in acting as a structural analog of these tRNA molecules, clindamycin impairs peptide chain initiation and may stimulate dissociation of peptidyl-tRNA from bacterial ribosomes. The mechanism through which topical clindamycin treats acne vulgaris is unclear, but may be related to its activity against _Propionibacterium acnes_, a bacteria that has been associated with acne.
Clindamycin may be bacteriostatic or bactericidal in action, depending on the concentration of the drug attained at the site of infection and the susceptibility of the infecting organism. Clindamycin palmitate hydrochloride and clindamycin phosphate are inactive until hydrolyzed to free clindamycin. This hydrolysis occurs rapidly in vivo. Clindamycin appears to inhibit protein synthesis in susceptible organisms by binding to 50S ribosomal subunits; the primary effect is inhibition of peptide bond formation. The site of action appears to be the same as that of erythromycin, chloramphenicol, and lincomycin.
Clindamycin binds exclusively to the 50S subunit of bacterial ribosomes and suppresses protein synthesis.
... Clindamycin is not a substrate for macrolide efflux pumps, and strains that are resistant to macrolides by this mechanism are susceptible to clindamycin.

C18H33CLN2O5S

424.98

424.179

18323-44-9

Clindamycin hydrochloride;21462-39-5;Clindamycin phosphate;24729-96-2;Clindamycin-d3 hydrochloride;1356933-72-6;Clindamycin-13C,d3;2140264-63-5;Clindamycin hydrochloride monohydrate;58207-19-5

446598

Yellow, amorphous solid

1.3±0.1 g/cm3

628.1±55.0 °C at 760 mmHg

141 - 143ºC

333.6±31.5 °C

0.0±4.2 mmHg at 25°C

1.574

1.83

4

7

7

27

502

9

CCC[C@@H]1C[C@H](N(C1)C)C(N[C@@H]([C@@H]2[C@H](O)[C@H](O)[C@@H](O)[C@@H](SC)O2)[C@@H](Cl)C)=O

KDLRVYVGXIQJDK-AWPVFWJPSA-N

InChI=1S/C18H33ClN2O5S/c1-5-6-10-7-11(21(3)8-10)17(25)20-12(9(2)19)16-14(23)13(22)15(24)18(26-16)27-4/h9-16,18,22-24H,5-8H2,1-4H3,(H,20,25)/t9-,10+,11-,12+,13-,14+,15+,16+,18+/m0/s1

(2S,4R)-N-((1S,2S)-2-chloro-1-((2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-(methylthio)tetrahydro-2H-pyran-2-yl)propyl)-1-methyl-4-propylpyrrolidine-2-carboxamide

U-21251 U 21251 ClindamycinCleocin, Clinacin, Dalacin

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Note: This product requires protection from light (avoid light exposure) during transportation and storage.

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

DMSO : ~125 mg/mL (~294.13 mM)

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.)