F

5-aminosalicylate (5ASA) medications Drugs
taken to treat INFLAMMATORY BOWEL DISEASE(IBD),
an autoimmune disorder that causes mild to
severe INFLAMMATIONand irritation to the COLON
(bowel). People who have IBD typically experi-
ence alternating periods of exacerbation and
REMISSION; in severe IBD the symptoms are often
debilitating. The aminosalicylates, or 5ASAs,
appear to work by suppressing the local IMMUNE
RESPONSEin the mucosal lining of the SMALL INTES-
TINEand COLON.
Though researchers do not fully understand
what causes IBD, they do know there are high
levels of LEUKOTRIENESand PROSTAGLANDINSin the
BLOODcirculation when IBD flares up. Researchers
believe the 5ASA medications block these bio-
chemicals from release, thus inhibiting inflamma-
tion. These drugs may also block the actions of
TUMOR NECROSIS FACTORS(TNFS), CYTOKINESthat also
participate in the inflammatory response.

5-AMINOSALICYLATE (5ASA) MEDICATIONS

balsalazide (Colazal)
mesalamine (Asacol, Canasa, Pentasa, Rowasa)
olsalazine (Dipentum)
sulfasalazine (Azulfidine)

The 5ASAs are most effective when adminis-
tered via rectal suppository or ENEMA, or by
absorption-delayed oral medications (drugs that
are specially coated to dissolve in the SMALL INTES-
TINErather than the STOMACH) as these ROUTES OF
ADMINISTRATION deliver the drug directly to the
involved tissues. Pharmacologically, the 5ASAs are
similar to aspirin. The most common side effects
include HEADACHE, NAUSEA, andRASH(which occur
most frequently with sulfasalazine and not so
much with the other 5ASAs). The 5ASAs are

effective for treating symptoms during exacerba-

tions as well as for extending remission (prevent-

ing symptoms from reemerging).

See also AUTOIMMUNE DISORDERS; CORTICOSTEROID

MEDICATIONS; NONSTEROIDAL ANTI-INFLAMMATORY

DRUGS(NSAIDS).

food allergies Hypersensitivity reactions to con-

sumed foods. Food allergies affect about nine mil-

lion Americans, two thirds of them children under

the age of six. Allergies to peanuts, milk, wheat,

shellfish, strawberries, and eggs are among the

most common. Some people are allergic to preser-

vatives or other substances used to prepare foods.

Children tend to outgrow many food allergies;

however, many adults develop food allergies later

in life.

Unpleasant responses—such as STOMACHirrita-

tion, FLATULENCE(intestinal gas), and episodes of

DIARRHEA—to certain foods are common but are

not necessarily food allergies. An ALLERGYresults in

the activation of antibodies that triggers a HYPER-

SENSITIVITY REACTION, an excessive IMMUNE RESPONSE

in which the IMMUNE SYSTEMresponds to a particu-

lar food as though it were a harmful substance.

The COMPLEMENT CASCADEfloods the BLOODcircula-

tion with antibodies, mast cells release HISTAMINE

and PROSTAGLANDINS, and various types of leuko-

cytes mobilize to attack the ALLERGEN.

Though some symptoms may be the same—

such as stomach upset and diarrhea—the differ-

ence between food intolerance and food allergy

can literally be life threatening: ANAPHYLAXIS, the

most severe kind of hypersensitivity reaction, is an

ever-present danger with food allergies. Of partic-

ular concern are ingredients that may not be obvi-

ous, such as peanut oil or soy, and may be present

in processed foods as cross-contaminants.

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