RESEARCH - Pharmacokinetics of oral MTX in patients with RA

[Guest guest]

Pharmacokinetics of Oral Methrotrexate in Patients With Rheumatoid Arthritis

Medscape

Posted 01/16/2009

Methotrexate (MTX) is commonly used to treat rheumatoid arthritis (RA)

and is suggested as the " anchor " drug in treating the disease. Despite

its widespread use, the understanding of its mechanism of action and

pharmacokinetics is limited. Since joint damage occurs early in the

course of RA and is largely irreversible, understanding the time it

takes for stable levels of MTX to be reached could be useful in

effectively controlling RA and preventing long-term damage. A new

study examining levels of MTX metabolites in red blood cells was

published in the November issue of Arthritis & Rheumatism

(http://www3.interscience.wiley.com/journal/76509746/home).

MTX is normally taken orally and is rapidly taken up into a variety of

cells, including red blood cells, where it remains long after being

eliminated from blood serum. Once inside red blood cells, the drug can

assume up to five different forms, which are known as MTXGlu1-5 (MTX

polyglutamates) These can be measured inside red blood cells and are

thought to be representative of concentrations within other cells,

such as lymphocytes. Within the cell, MTX polyglutamates bind to and

inhibit several important enzymes, playing a role in a number of

anti-inflammatory actions and pathways. The dose of MTX varies and is

unpredictable from patient to patient, but because it disappears

rapidly from blood plasma, measurement in plasma can't be used to

monitor concentrations of the drug. However, MTX polyglutamate

concentrations can be measured in red blood cells. Patients with RA

are normally started on low doses of MTX, with increasing amounts

based on response to treatment, but valuable time may be lost with

this method, resulting in unnecessary joint damage.

*********************************************

Read the entire article here:

http://www.medscape.com/viewarticle/585493

Not an MD

[Guest guest]

Which reminds me, occassionally before being diagnosed I gave blood when demand

became critical, being O-Neg, which is fairly common no one was that excited.

But now I am wondering if those of us with RA should give blood, and/or would

they even accept it? Just curious.

Stan

Seattle, Foggy, very foggy.

-------------- Original message --------------

From: " " <Rheumatoid.Arthritis.Support@...>

Pharmacokinetics of Oral Methrotrexate in Patients With Rheumatoid Arthritis

Medscape

Posted 01/16/2009

Methotrexate (MTX) is commonly used to treat rheumatoid arthritis (RA)

and is suggested as the " anchor " drug in treating the disease. Despite

its widespread use, the understanding of its mechanism of action and

pharmacokinetics is limited. Since joint damage occurs early in the

course of RA and is largely irreversible, understanding the time it

takes for stable levels of MTX to be reached could be useful in

effectively controlling RA and preventing long-term damage. A new

study examining levels of MTX metabolites in red blood cells was

published in the November issue of Arthritis & Rheumatism

(http://www3.interscience.wiley.com/journal/76509746/home).

MTX is normally taken orally and is rapidly taken up into a variety of

cells, including red blood cells, where it remains long after being

eliminated from blood serum. Once inside red blood cells, the drug can

assume up to five different forms, which are known as MTXGlu1-5 (MTX

polyglutamates) These can be measured inside red blood cells and are

thought to be representative of concentrations within other cells,

such as lymphocytes. Within the cell, MTX polyglutamates bind to and

inhibit several important enzymes, playing a role in a number of

anti-inflammatory actions and pathways. The dose of MTX varies and is

unpredictable from patient to patient, but because it disappears

rapidly from blood plasma, measurement in plasma can't be used to

monitor concentrations of the drug. However, MTX polyglutamate

concentrations can be measured in red blood cells. Patients with RA

are normally started on low doses of MTX, with increasing amounts

based on response to treatment, but valuable time may be lost with

this method, resulting in unnecessary joint damage.

*********************************************

Read the entire article here:

http://www.medscape.com/viewarticle/585493

Not an MD

[Guest guest]

I have been wondering about whether we should give blood also.  They have blood

drives where I work often and I have not participated for not knowing.

, NY

________________________________

From: " stanpfister@... " <stanpfister@...>

Sent: Sunday, January 18, 2009 12:49:15 PM

Subject: Re: [ ] RESEARCH - Pharmacokinetics of oral MTX in patients

with RA

Which reminds me, occassionally before being diagnosed I gave blood when demand

became critical, being O-Neg, which is fairly common no one was that excited.

But now I am wondering if those of us with RA should give blood, and/or would

they even accept it? Just curious.

Stan

Seattle, Foggy, very foggy.

------------ -- Original message ------------ --

From: " " <Rheumatoid.Arthriti s.Support@ gmail.com>

Pharmacokinetics of Oral Methrotrexate in Patients With Rheumatoid Arthritis

Medscape

Posted 01/16/2009

Methotrexate (MTX) is commonly used to treat rheumatoid arthritis (RA)

and is suggested as the " anchor " drug in treating the disease. Despite

its widespread use, the understanding of its mechanism of action and

pharmacokinetics is limited. Since joint damage occurs early in the

course of RA and is largely irreversible, understanding the time it

takes for stable levels of MTX to be reached could be useful in

effectively controlling RA and preventing long-term damage. A new

study examining levels of MTX metabolites in red blood cells was

published in the November issue of Arthritis & Rheumatism

(http://www3. interscience. wiley.com/ journal/76509746 /home).

MTX is normally taken orally and is rapidly taken up into a variety of

cells, including red blood cells, where it remains long after being

eliminated from blood serum. Once inside red blood cells, the drug can

assume up to five different forms, which are known as MTXGlu1-5 (MTX

polyglutamates) These can be measured inside red blood cells and are

thought to be representative of concentrations within other cells,

such as lymphocytes. Within the cell, MTX polyglutamates bind to and

inhibit several important enzymes, playing a role in a number of

anti-inflammatory actions and pathways. The dose of MTX varies and is

unpredictable from patient to patient, but because it disappears

rapidly from blood plasma, measurement in plasma can't be used to

monitor concentrations of the drug. However, MTX polyglutamate

concentrations can be measured in red blood cells. Patients with RA

are normally started on low doses of MTX, with increasing amounts

based on response to treatment, but valuable time may be lost with

this method, resulting in unnecessary joint damage.

************ ********* ********* ********* ******

Read the entire article here:

http://www.medscape .com/viewarticle /585493

Not an MD

[Guest guest]

Betty and I have tried donating blood but we're refused every time. She is

diabetic and I have RA, so that and the meds to control them negates our

blood offerings.

Dennis in eastexas

On Mon, Jan 19, 2009 at 4:52 AM, Bloomquist <skaye81@...>wrote:

> I have been wondering about whether we should give blood also. They

> have blood drives where I work often and I have not participated for not

> knowing.

>

> , NY

>

> ________________________________

> From: " stanpfister@... <stanpfister%40comcast.net> " <

> stanpfister@... <stanpfister%40comcast.net>>

> < %40>

> Sent: Sunday, January 18, 2009 12:49:15 PM

> Subject: Re: [ ] RESEARCH - Pharmacokinetics of oral MTX in

> patients with RA

>

> Which reminds me, occassionally before being diagnosed I gave blood when

> demand became critical, being O-Neg, which is fairly common no one was that

> excited. But now I am wondering if those of us with RA should give blood,

> and/or would they even accept it? Just curious.

>

> Stan

> Seattle, Foggy, very foggy.

>

> .

>

>

>

[Guest guest]

I have diabetes and RA, and have also had cancer, so I don't even try

to give blood.

Sue

On Jan 19, 2009, at 11:57 AM, Dennis W wrote:

> Betty and I have tried donating blood but we're refused every time.

> She is

> diabetic and I have RA, so that and the meds to control them negates

> our

> blood offerings.

>

[Guest guest]

That's good to know, and I guess it was a good question being that it could save

some time and/or embrassment. I generally don't announce in a public forum that

there's something wrong with me, or confirm what they already know, LOL.

Stan,

Seattle, cloudy, foggy, and sun - only here!

--------- Re: [ ] RESEARCH - Pharmacokinetics of oral MTX in

> patients with RA

>

> Which reminds me, occassionally before being diagnosed I gave blood when

> demand became critical, being O-Neg, which is fairly common no one was that

> excited. But now I am wondering if those of us with RA should give blood,

> and/or would they even accept it? Just curious.

>

> Stan

> Seattle, Foggy, very foggy.

>

> .

>

>

>