If you patient is taking any of the following drugs, they could be at risk of serotonin syndrome if you give methylene blue.
http://www.fda.gov/Drugs/DrugSafety/ucm263190.htm
Tables -Psychiatric medications with serotonergic activity
Selective Serotonin Reuptake Inhibitors (SSRIs)
Generic nameFound in Brand name(s)
paroxetinePaxil, Paxil CR, Pexeva
fluvoxamineLuvox, Luvox CR
fluoxetineProzac, Sarafem, Symbyax
sertralineZoloft
citalopramCelexa
escitalopramLexapro
Serotonin-Norepinephrine Reuptake Inhibitors (SNRIs)
Generic nameFound in Brand name(s)
venlafaxineEffexor, Effexor XR
desvenlafaxinePristiq
duloxetineCymbalta
Tricyclic Antidepressants (TCAs)
Generic nameFound in Brand name(s)
amitriptylineAmitid, Amitril, Elavil, Endep, Etrafon, Limbitrol, Triavil
desipramineNorpramin, Pertofrane
clomipramineAnafranil
imipramineTofranil, Tofranil PM, Janimine, Pramine, Presamine
nortriptylinePamelor, Aventyl hydrochloride
protriptylineVivactil
doxepinSinequan, Zonalon, Silenor
trimipramineSurmontil
Monoamine Oxidase Inhibitors (MAOIs)
Generic nameFound in Brand name(s)
IsocarboxazidMarplan
PhenelzineNardil
SelegilineEmsam, Eldepryl, Zelapar
TranylcypromineParnate
Other Psychiatric Medications
Generic nameFound in Brand name(s)
amoxapineAsendin
maprotilineLudiomil
nefazodoneSerzone
trazodoneDesyrel, Oleptro, Trialodine
bupropionWellbutrin, Wellbutrin SR, Wellbutrin XL, Zyban, Aplenzin
buspironeBuspar
vilazodoneViibryd
mirtazapineRemeron, Remeron Soltab