Biomaterial Database

Variability of methotrexate pharmacokinetics and pharmacodynamics. 1988

A H Dawson, and J J Grygiel

Department of Clinical Pharmacology, Royal Newcastle Hospital, N.S.W., Australia.

It is apparent that MTX is a useful agent in the treatment of rheumatoid arthritis resistant to first and second line therapies. However, despite its long term use in this disease, considerable uncertainty exists about the basic pharmacokinetics of low dose oral MTX and therefore about its pharmacodynamics. It is probable that when MTX is re-examined with the help of modern analytical technology in a rheumatoid setting that pharmacological insights to the variability in dose-response relationships for efficacy and certain toxicities may emerge. There is still considerable uncertainty of the hepatotoxic potential of MTX. Further investigation of the accumulation of active polyglutamated MTX in liver may throw light on the likelihood of promoting iatrogen disease and perhaps the contribution of oral administration to this problem. Finally, examination of dose-response relationship utilising accurate pharmacokinetics may help to establish guidelines for the safe and effective usage of MTX in rheumatoid arthritis.

UI	MeSH Term	Description	Entries
D008099	Liver	A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.	Livers
D008168	Lung	Either of the pair of organs occupying the cavity of the thorax that effect the aeration of the blood.	Lungs
D008727	Methotrexate	An antineoplastic antimetabolite with immunosuppressant properties. It is an inhibitor of TETRAHYDROFOLATE DEHYDROGENASE and prevents the formation of tetrahydrofolate, necessary for synthesis of thymidylate, an essential component of DNA.	Amethopterin,Methotrexate Hydrate,Methotrexate Sodium,Methotrexate, (D)-Isomer,Methotrexate, (DL)-Isomer,Methotrexate, Dicesium Salt,Methotrexate, Disodium Salt,Methotrexate, Sodium Salt,Mexate,Dicesium Salt Methotrexate,Hydrate, Methotrexate,Sodium, Methotrexate
D001853	Bone Marrow	The soft tissue filling the cavities of bones. Bone marrow exists in two types, yellow and red. Yellow marrow is found in the large cavities of large bones and consists mostly of fat cells and a few primitive blood cells. Red marrow is a hematopoietic tissue and is the site of production of erythrocytes and granular leukocytes. Bone marrow is made up of a framework of connective tissue containing branching fibers with the frame being filled with marrow cells.	Marrow,Red Marrow,Yellow Marrow,Marrow, Bone,Marrow, Red,Marrow, Yellow
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000284	Administration, Oral	The giving of drugs, chemicals, or other substances by mouth.	Drug Administration, Oral,Administration, Oral Drug,Oral Administration,Oral Drug Administration,Administrations, Oral,Administrations, Oral Drug,Drug Administrations, Oral,Oral Administrations,Oral Drug Administrations
D001172	Arthritis, Rheumatoid	A chronic systemic disease, primarily of the joints, marked by inflammatory changes in the synovial membranes and articular structures, widespread fibrinoid degeneration of the collagen fibers in mesenchymal tissues, and by atrophy and rarefaction of bony structures. Etiology is unknown, but autoimmune mechanisms have been implicated.	Rheumatoid Arthritis
D001682	Biological Availability	The extent to which the active ingredient of a drug dosage form becomes available at the site of drug action or in a biological medium believed to reflect accessibility to a site of action.	Availability Equivalency,Bioavailability,Physiologic Availability,Availability, Biologic,Availability, Biological,Availability, Physiologic,Biologic Availability,Availabilities, Biologic,Availabilities, Biological,Availabilities, Physiologic,Availability Equivalencies,Bioavailabilities,Biologic Availabilities,Biological Availabilities,Equivalencies, Availability,Equivalency, Availability,Physiologic Availabilities
D013280	Stomatitis	INFLAMMATION of the soft tissues of the MOUTH, such as MUCOSA; PALATE; GINGIVA; and LIP.	Oral Mucositis,Mucositis, Oral,Oromucositis,Mucositides, Oral,Oral Mucositides,Oromucositides,Stomatitides