Pyrithione

127.16400

127.16

214-329-4

6GK82EC25D

179790

DTXSID4048010|DTXSID00149908

C61916

2933399090

57.25000

1.45490

1.43g/cm3

68-70 °C

253.8ºC at 760mmHg

107.3ºC

1.732

Soluble in cold water (Zinc salt)

0.00275mmHg at 25°C

P261, P264, P270, P271, P280, P301+P312, P302+P352, P304+P340, P305+P351+P338, P312, P321, P330, P332+P313, P337+P313, P362, P403+P233, P405, P501

H302

|Danger|H301 (95.45%): Toxic if swallowed [Danger Acute toxicity, oral]|P261, P264, P270, P271, P280, P301+P310, P302+P352, P304+P340, P305+P351+P338, P312, P321, P330, P332+P313, P337+P313, P362, P403+P233, P405, and P501|Aggregated GHS information provided by 44 companies from 4 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

Acute oral LD50 value is 177 mg/kg in rat and 160 mg/kg in mouse. Acute dermal LD50 was 100 mg/kg in rabbit [MSDS].

Indicated for the treatment of dandruff and seborrheic dermatitis.

Pyrithione zinc has a broad antimicrobial spectrum of activity, including fungi, gram-positive and gram-negative bacteria. Pyrithione zinc is effective against Malassezia and all other fungi, especially the Malassezia species found on scalp. In patients with dandruff, treatment with pyrithione zinc reduced the amount of fungus on the scalp, which reduces the amount of free fatty acids, thereby reducing scalp flaking and itch.

Substances that destroy fungi by suppressing their ability to grow or reproduce. They differ from FUNGICIDES, INDUSTRIAL because they defend against fungi present in human or animal tissues. (See all compounds classified as Antifungal Agents.)

Following oral ingestion, only the pyrithione moiety is absorbed. Less than 1% of administered zinc pyrithione is absorbed from the skin. Radioabeled Zn pyrithione administered to rats, rabbits and monkeys, either orally or via intraperitoneal injection were absorbed into circulatin to extent of 80-90%.|The major route of elimination from the body after oral administration in rat was urine, with S-glucuronides of 2-mercaptopyridine-N-oxide being the major metabolites and 2-mercaptopyridine-N-oxide as the minor metabolite. Following oral administration, the majority of zinc is eliminated in the feces. Upon dermal administration, >90% of recovery was obtained from washings of the application site of pigs. Urinary excretion was 3% in animals with intact skin.

After oral administration in rabbits, rats, monkeys, and dogs, pyrithione zinc is biotransformed into 2-pyridinethiol 1-oxide S-glucuronide and 2-pyridinethiol S-glucuronide.

Inhibition of fungal growth by pyrithione zinc is linked to increased copper uptake and cellular levels of copper, which is demonstrated by decreased CTR1-lacZ expression and slightly increased CUP1-lacZ expression in affected microorganisms. The coordination complex of pyrithione zinc dissociates, and pyrithione ligand forms a CuPT complex from available extracellular copper in the target organism. Pyrithione acts as an ionophore, interacting nonspecifically with the plasma membrane to shuttle copper into the cell, and facilitates copper transport across intracellular membranes. Copper may be shuttled into the mitochondria. Copper inactivates iron-sulfur (Fe-S) cluster-containing proteins via a mechanism similar to that described for copper-induced growth inhibition in bacteria. Decreased activity of Fe-S proteins leads to inhibition of fungal metabolism and fungal growth. Pyrithione zinc has been shown to slightly increase the levels of zinc.

1-hydroxypyridine-2-thione

2-Pyridinethiol, 1-oxide: ACTIVE