Posted by
Pioneers on Tuesday, April 20, 2010 2:13:27 AM
Benzimidazoles were originally developed as plant fungicides and later
as veterinary and human anthelmintics. The family of benzimidazoles
with anthelmintic activity includes thiazolyl benzimidazoles and
benzimidazole carbamates. The benzimidazoles show a broad spectrum of
activity against helminth parasites. Well known benzimidazoles with
activity against helminths are for example thiabendazole; cambendazole;
and benzimidazole carbamates, such as parbendazole (U.S. Pat. No.
3,480,642), mebendazole (U.S. Pat. No. 3,657,267), flubendazole (U.S.
Pat. No. 3,657,267), fenbendazole (U.S. Pat. No. 3,954,791),
oxfendazole (U.S. Pat. No. 3,929,821), oxibendazole (U.S. Pat. No.
3,574,845),
albendazole
(U.S. Pat. No. 3,915,986), ricobendazole ( albendazole sulfoxide) (U.S.
Pat. No. 3,915,986) and luxabendazole (U.S. Pat. No. 4,639,463), all of
which differ in the substituents on the parent benzimidazole nucleus.
Benzimidazoles are believed to owe their activity to the fact that they
block the polymerization of beta-tubulin into microtubules. This
affects the transport functions of cells within the parasite and
ultimately kills the parasite.
Phenylguanidine prodrugs that are metabolically transformed into
anthelmintic benzimidazoles have also been developed. Febantel (U.S.
Pat. No. 3,993,682), for example, is a prodrug that is converted into
fenbendazole, and netobimin (U.S. Pat. No. 4,406,893) yields
albendazole. Albendazole is an anthelmintic medication used in the
treatment of infections of the body caused by tapeworms. The medication
works by preventing newly hatched worms from growing and multiplying
from within the body. As with most anthelmintic medications, there are
certain side effects associated with treatment.
Efforts regarding benzimidazole prodrugs were undertaken in the context
of the use of the benzimidazoles in the combat of systemic infections,
for example with the larval stage of the cestodes, Echinococcus
multicularis and E. granulosis . In these cases plasma and tissue
levels of the drugs are important since, in order to act systemically,
the benzimidazoles have to be taken up into the bloodstream.
Certain albendazole prodrugs are described by Hernández-Luis et al. in
Bioorganic & Medicinal Chemistry Letters, 11, 1359-1362, 2001.
Hernández-Luis et al. attempted to enhance the solubility of
albendazole by synthesizing three N-acyl and two N-alkoxycarbonyl
derivatives. These derivatives were developed mainly in the context of
the use of
albendazole products
for some tissue dwelling infestations such as trichinellosis, hydrated
disease (echinococcsis) and neurocysticerosis, where high doses and
long treatment are required due to the poor solubility and absorption
of albendazole. Before taking Albendazole, tell your doctor if you have
ever suffered from liver disease or any type of liver condition as you
may not be able to use this medication. This medication is classified
as FDA pregnancy category C and it may cause harm to an unborn baby. It
is also unknown whether or not the drug is secreted into breast milk,
and it is recommended to use extreme caution if you are nursing while
using this medication. Also, consult with your doctor if you have ever
had an allergic reaction to any type of food or medication before using
this drug.
Mannich bases of albendazole and fenbendazole were prepared by
Dhaneshwar et al., Indian drugs, 28(1), 24-26, 1990, using various
secondary amines such as dimethylamine, dipropylamine, pyrrolidine,
piperazine, etc. Further Mannich bases are described in Garst et al.
(U.S. Pat. No. 6,093,734). However, actual activity has not been
demonstrated for the Mannich bases, and these derivative show very low
stability in water.
A water soluble prodrug of
albendazole manufacturer exists, namely netobimin. But although netobimin is water soluble, it has been reported to cause embryonal toxicity.
In WO9312124 another class of benzimidazoles is discussed, namely
substituted
2-[[(3,4-dialkoxy-2-pyridinyl)-methyl]sulfonyl]-1(H)-benzimi
dazole-1-yl compounds. These benzimidazoles are gastric acid secretion
inhibitors (proton pump inhibitors) and structurally resemble
well-known gastric acid secretion inhibitors like omeprazole and
lansoprazole. In contrast to the benzimidazole carbamates, which are
practically insoluble in water, the benzimidazole proton pump
inhibitors are markedly more soluble in water. For example, omeprazole
has a solubility of 500 μg/mL Unfortunately, there are a number of side
effects associated with using albendazole. Some of these side effects
include nausea, stomach pain, vomiting, temporary hair loss, dizziness,
headache, unusual weakness, easy bruising and bleeding, sore throat,
fever, skin rash, body aches, flu-like symptoms and severe skin
blistering. While these are considered the most common side effects
associated with this drug, they only affect a small amount of users.
If you are allergic to albendazole or mebendazole, you should not use
this medication as it can cause severe internal damage to some users.
This medication has been known to lower the body's ability to fight
infection and it is recommended that users stay away from anyone with
an illness or disease until they have completed treatment. Regular
blood tests will be required to ensure that your blood-cell levels
remain at a healthy level throughout the course of your treatment, so
consult with your doctor about an appropriate schedule.The compounds of
the invention are highly soluble and stable in water. For example, a
mixture of (5- and
6-phenylsulfanyl-1-phosphonooxymethyl-1(H)-benzoimidazol-2-y
l)-carbamic acid methyl esters di-sodium salts has a solubility in
water of 132 mM (67 g/L). Furthermore, other compounds according to the
invention such as N-phosphonooxymethyl substituted albendazole,
mebendazole, flubendazole and luxabendazole sodium salts have aqueous
solubilities of at least 50 mM.
Always use
albendazole tablets
exactly as it was prescribed by your doctor and never in dosages larger
than what has been recommended on the label. The medication is
administered in tablet form and should be taken with food and a full
glass of water. Alebendazole is sometimes used as a cycled medication,
meaning that treatment may occur for four weeks followed directly by
two weeks of non-treatment. Store this medication away from sources of
moisture and at room temperature for the best results.If you experience
any of the above side effects, contact your doctor immediately.
If an overdose is suspected, contact the poison control center at (800)
222-1222 and head directly to the nearest emergency room.
Albendazole is meant in the treatment of the above ailments only and
should not be used for any other medical purpose unless specifically
prescribed by a doctor.