Home > Flashcards > Print Preview
The flashcards below were created by user
on FreezingBlue Flashcards. What would you like to do?
3 types of drugs to Tx pain?
- 1. strong narcotic - morphine
- 2. mild narcotic - codeine
- 3. mixed agonist-antagonists - pentazocine/Talwin
Advantages of morphine use other than for pain?
- 1. can relieve anxiety
- 2. can decrease workload of the heart
EX: pulmonary edema
2 drug classifications for pain management?
1. opiod analgesics / narcotics
Action of opioid analgesics?
act on CNS to interfere with the pain experience
Use for opioid analgesics?
Tx moderate to severe pain
Action of NSAIDS?
act in the PNS - interferes with prostaglandin synthesis and prevents the transmission of pain impulses
Why does morphine cause resp depression?
Morphine should be given cautiously/contraindicated with what types of drugs?
CNS depressants including alcohol
Important consideration when giving narcotics r/t CNS effects?
should not drive etc until know how the drug will effect person
WHO 3 step analgesic ladder?
- 1. mild pain med: EX ASA, acet
- 2. moderate: codeine, hydrocodone
- 3. severe: nonopioid- opiod: morphine, fentanyl
What is the standard measure of pain relief?
10 mg parenteral morphine = analgesic dose
2 actions that must be taken when giving narcotic analgesics?
- 1. document # of doses on hand
- 2. document partial/wasted doses
What must be documented when giving a pain med?
- 1. pain scale, location, and description
- 2. pain reassessment
4 types of pain morphine is used for?
- 1. moderate - severe acute or chronic pain
- 2. postoperative pain
- 3. pain non-responsive to non-narcotics
- 4. MI pain
Most important consideration with methotrexate/Rheumatrex and other DMARDS?
causes bone marrow dysfunction: anemia, thrombocytopenia, and leukopenia
risk for infection and bleeding
Non-pain uses for morphine?
- 1. dyspnea r/t acute L ventricular failure & pulmonary edema
- 2. preoperative
- 3. sedation
- 4. anxiety relief
- 5. facilitate induction anesthesia
- 6. reduce amnt of anesthetic needed
Routes of admin for morphine?
may be used by almost any route - may be used in PCA
Imp consideration for pt on morphine PCA pump?
only pt should admin dose
Onset of action for morphine?
15 to 30 min
Duration of action for morphine?
3 to 7 h
What will occur if ibu is taken with lithium?
lithium toxicity is increased
5 contraindications/precautions for morphine?
- 1. pre-existing respiratory depression
- 2. acute or severe bronchial asthma
- 3. upper airway obstruction
- 4. increased intracranial pressure
- 5. CNS depression
Why is morphine contraindicated with increased ICP?
morphine has a stimulatory effect on the SC
8 adverse effects of morphine?
- 1. resp depression - LIFE THREATENING
- 2. bradycardia
- 3. hypotension
- 4. constipation
- 5. CNS effects
Antidote for opiates?
Onset of action for naloxone?
IV 2 min
Imp consideration about half life of naloxone/Narcan?
has a short half life - may wear off before the opiate does and have CNS depressant effects again
How does narcan/naloxone affect pain control?
will reverse effects of pain control if dose is sufficient
2 key issues of morphine admin?
- 1. maintain RR w/in 12 to 20 BPM
- 2. minimal effects of constipation
How can being immobile in the hospital exacerbate AE of morphine?
can exacerbate constipation
What 2 things should be assessed before admin of morphine?
RR & BP
What will the RR & BP of a person in pain be like?
may be high
6 nursing interventions to prevent respiratory depression?
- 1. pulse ox
- 2. turn, cough, deep breathe
- 3. reposition frequently
- 4. maintain on side but if supine remove pillow
- 5. have emergency respiratory equip available
- 6. keep naloxone on hand
Drug of choice for infants and CH with flu or flu-like S/S?
3 nursing interventions for constipation?
- 1. increase fiber and water/fluid intake
- 2. ambulate (with assistance)
- 3. stool softeners or laxatives prn
When should morphine not be used during pregnancy?
not to be used during labor if expecting a premature infant and not to be used with a premature infant
Drug interactions with morphine?
other CNS depressants
EX: versed and morphine
What will occur if ibu is taken with loop diuretics like furosemide?
reduces antidiuretic effect
What should the nurse know the location of before giving a med>?
If RR is < ____, hold morphine and call MD
body accustomed to effects and need increased dose to get therapeutic effect
may switch meds
abuse of alc, Rx drugs, or illicit drugs can increase tolerance to pain meds
may need increased dose
W/D or abstinence syndrome occurs when med is stopped
When is physical dependence usually seen in morphine?
when taking longer than 3 months
4 S/S of W/D from an opiate?
- 1. restless - may say don't feel right
- 2. tachypnea
- 3. hypertension
- 4. tachycardia
What will occur if ibu is taken with aminoglycoside antibiotics?
GFR is reduced and the aminoglycoside will accumulate
What will occur if ibu is taken with a beta blocker?
impairs antihypertensive effects of the beta blocker
compulsive use for secondary gain, not for pain control
tolerate pain w/out verbal complaints
British, German, & Asian
4 Expressive cultures?
- 1. Spanish
- 2. Italian
- 3. Latin
- 4. white American adults
same risks and info as morphine
Oxycodone is combined with either ___ or ___.
ASA or acet
Serious adverse effect of oxycodone?
can cause adverse effects r/t acet and ASA content
calculate daily intake of ASA & acet
What pt teaching needs to be done about oxycodone?
teach pt about risk for liver toxicity if they take too much
Type of pain fentanyl is used for?
persistent, moderate to severe chronic pain
When will a pt obtain full pain relief after a fentanyl patch has been applied?
TAKES APPROX 24 H
3 drug to drug interactions with fentanyl?
What will occur?
- 1. P450 inhibitors
- 2. ketoconazole - antifungal
- 3. Clarithromycin/Biaxin - anti-infective
all increase levels of fentanyl and increase AE and resp depression
6 considerations when applying fentanyl/Duragesic patch?
- 1. wear gloves
- 2. tear - don't cut
- 3. Apply to non-irritated, smooth, and hairless skin
- 4. Clip - don't shave
- 5. No soap, creams, alc, oils, or lotions
- 6. hold patch in place X 30 seconds
Why should fentanyl not be applied to irritated or broken skin?
can increase absorption and AE
4 application sites for fentanyl/Duragesic patch?
- 1. chest
- 2. back
- 3. flank
- 4. upper arm
How often should a fentanyl patch be replaced?
q 72 h
What occurs when acet is taken with warfarin?
serum warfarin levels are increased
Pt teaching for fentanyl/Duragesic patch?
avoid heat: heating pads, sun lamps, elec blankets, heated water beds, hot tubs, and saunas
can increase absorption of the drug
How should removed duragesic/fentanyl patch be discarded?
flush down toilet, put in sharps, or put plastic from container on the patch and throw away
Most important consideration when applying a duragesic/fentanyl patch?
make sure to take off the old patch
What should be documented when applying a duragesic patch?
where it was placed
iontopohoretic transdermal system
Each activation of IONSYS provides ____ mcg fentanyl over a ____ min period.
What will occur if ibu is taken with a selective serotoinin reuptake inhibitor?
increases risk of upper GI bleed
How is the IONSYS operated?
- 1. press top button twice firmly w/in 3 seconds
- 2. hear beep sounds and red light comes on to indicate dose released
- 3. red light remins lit during 10 min dosing time
Max dose of fentanyl IONSYS?
max of 6 - 40mcg doses per hour
How long does each IONSYS system work?
24 h or 30 doses whichever comes first
IONSYS is for ____ use only.
3 uses for methadone?
- 1. pain control
- 2. prevent W/D S/S from heroin
- 3. maintenance Tx for narcotic abuse
2 types of mild narcotic agonists?
codeine and hydrocodone
2 uses for codeine?
- 1. control mild to moderate pain in adults and CH
- 2. cough suppressant and dries up secretions
2 routes for codine?
oral and parenteral
What 2 drugs is codeine co-admin with?
ASA & acet
Why is codeine co-admin with other analgesics?
provides additive analgesic effect and permits lower dose of codeine
3 contraindications and precautions with codine?
- 1. asthma and emphysema
- 2. avoid if delivery of premature infant is expected
- 3. increase intracranial pressure (head injury)
What will occur is ibu is taken with salicylates?
increases risk for GI or bleeding probs
Why is asthma, emphysema, & post surgery pt contraindicated with codeine?
can lead to accumulation of secretions and loss of resp reserve
codeine has drying effect on mm and can increase viscosity of secretions
AE of codeine?
same as morphine
less AE with low doses required for antitussive
Drug to drug interaction with codine?
histamine-2 receptor antagonists (cimetidine/Tagamet) increases risk for resp depression
Nursing assessment before admin codine?
RR less than 10 need to hold med
Hydrocodone may be co-admin with what drugs?
ASA, acet, ibu
What will occur if acet is taken with sulfinpyrazone/Anturane or hydantoin meds like dilantin?
increases risk for hepatotoxiciy
Imp consideration with prolonged hydrocodone admin?
ASA, ibu, and acet co-admin can cause kidney and liver toxicity with prolonged use
Analgesic of choice during preg/lactation?
3 narcotic agonist-antagonists?
- 1. pentazocine/Talwin
- 2. butorphanol/Stadol
- 3. nalbuphine/Nubain
Pentazocine/Talwin 5 uses?
- 1. moderate to severe pain
- 2. postop pain
- 3. pain during labor
- 4. premedication for anesthesia
- 5. supplement to surgical anesthetics
Pharmacokinetics consideration with pentazocine/Talwin?
high first-pass effect of hepatic met. -
Imp consideration when giving pentazocine/Talwin to a person who abuses opiates?
may precipitate a W/D syndrome b/c of antagonistic effect
2 contraindications/cautions with Talwin/pentazocine?
- 1. increase intracranial pressure
- 2. MI r/t increased workload of heart
2 AE of pentazocine/Talwin?
- 1. causes little resp depression b/c of antagonist action
- 2. euphoria
Antidote for salicylate poisoning?
there is no antidote
Street name for pentazocine/Talwin in ppl who abuse it?
Why is it abused?
T's and blues used as substitute for heroin and injected IV
Complication of abuse of pentazocine/Talwin?
pulmonary disease r/t blocking pulm arteries with particles from the tabs
Butorphanol/Stadol main difference from pentazocine/Talwin?
AE is somnolence
somnolence - state of near sleep, a strong desire for sleep, or sleeping for unusually long periods of time
Nalbuphine/Nubain is essentially the same as ____.
It has less _____ effects than morphine and less ____ AE than pentazocine.
What will occur if ibu is taken with an antifungal med like diflucan?
increases NSAID adverse effects
Important consideration when evaluating the effectiveness of mucomyst admin?
need to make sure if giving for mucous or to protect liver and kidneys as in acet OD
What type of pain is ASA especially used for?
Special uses for ASA?
- 1. neuralgia, myalgia, and arthralgia
- 2. postpartum pain
- 3. dental or oral surgery
- 4. dysmenorrhea
- 5. any arthritis
- 6. pleurisy
- 7. pericarditis in pt with sytemic lupus erythematosus SLE
When is ASA used in cardiac pt?
What is its action?
prevent or reduce risk of TIA, MI, & ischemic CVA
antiplatelet and anti-inflammatory effects
3 pharmacotherapeutic actions of ASA?
- 1. anti-pyretic
- 2. anti-inflammatory
- 3. pain relief
2 most imp contraindications of ASA?
- 1. bleeding disorders
- 2. CH with varicella/flu-like illness - Reye Syndrome
- 1. peptic ulcer disease
- 2. not given to pt on anticoagulation therapy except MI pt
- 3. gout
- 4. renal or liver impairment
2 adverse effects of ASA?
- 1. salicylism
- 2. salicylate poisoning
mild ASA toxicity r/t long-term or high-dose therapy
life-threatening event that has no antidote
3 Tx for salicylate poisoning?
- 1. gastric lavage
- 2. activated charcoal
- 3. life support
8 S/S of salicylate poisoning?
- 1. resp distress
- 2. F&E & pH imbalance
- 3. seizures
- 4. high temp
- 5. shock
- 6. coma
- 7. death
GI AE of prostaglandin inhibition that occurs with ASA and ibuprofen?
- 1. ulceration
- 2. perforation
- 3. bleeding
Pt education that should be done with sumatriptan/Imitrex?
- 1. instruct on S/S of ischemic events: MI & stroke
- 2. avoid driving or other activities that require alertness until response to med is known
Hematology AE that may occur with prostaglanding inhibition from ASA or ibu?
How long does the antithrombotic action of ASA last?
for the life of the platelet - 8 days
Admin of ASA in ER if having MI?
will chew the tablet
What 2 things should be checked before giving ASA?
- 1. platelets
- 2. active bleeding
When may heptotoxicity occur with ASA?
Why may renal toxicity occur with ASA or ibu?
prostaglandins that are inhibited by ASA & ibu normally inhibit vasoconstrictors
taking ASA vasoconstricts renal BF
What drug can cause induction of multiple sclerosis and optic neuritis?
CH < __ years of age should not take ASA.
When should ASA not be taken during pregnancy?
during the 3rd trimester r/t increased risk of maternal hemorrhage and AE fetal effects
What pt should be monitored carefully during ASA therapy?
pt over 60
Difference b/t salsalate/Disalcid & ASA?
same for anti-inflammatory but has no antiplatelet or antipyretic effects
Use for salsalate/Disalcid?
may be used by pt who cannot tolerate GI AE of ASA & pt at risk for anticoagulation
Action of NSAIDs?
inhibit COX 1 & 2 and prostaglandin synth
What will occur is ibu is taken with heparin?
increases risk of bleeding
How is the therapeutic efficacy of NSAIDs found?
based on pt response and cannot be predicted before use
Therapeutic uses for NSAIDs?
- 1. antiinflammatory
- 2. analgesic
- 3. antipyretic
Black Box Warning with ALL NSAIDs?
CV Thrombotic Events: increases risk for MI & stroke
Risk increases with duration of therapy
NSAIDs I don't know very well?
NSAIDs I know about?
- 1. diclofenac sodium/Voltaren
- 2. meloxicam/Mobic
- 3. nabumetone/Relafen
- 4. indomethacin
- 1. celecoxib/Celebrex
- 2. naproxen
- 3. ibuprofen/Motrin/Advil
- 4. ketorolac/Toradol
What type of pain is ibuprofen for?
mild - moderate
What is the drug misoprostol/Cytotec used for?
can be used to reduce GI upset with long-term NSAID therapy
4 common uses of ibu?
- 1. all types of arthritis
- 2. primary dysmenorrhea
- 3. migraine HA
- 4. fever
6 contraindications/cautious use of ibu?
- 1. active GI disease
- 2. renal or hepatic impairment
- 3. hemopoietic dysfunction
- 4. pre-existing coagulopathy
- 5. cardiac impairment
- 6. age > 60
Drug to drug interactions with ASA?
What will occur?
- 1. anticoagulants
- 2. oral hypoglycemics
- 3. insulin
ASA will increase the effects of this drug by binding to protein
2 illness EX that should not take ibu (cardiac)?
Why can ibu not be taken with active GI disease?
ibu can cause gastritis, GI bleeds, and ulceration
Why can ibu not be taken with hemopoietic dysfunction?
has effect on platelet functions & prolongs bleeding
Why can ibu/NSAIDs not be taken with cardiac impairment?
increased risk for MI and stroke
4 long-term AE effects of ibuprofen?
- 1. PUD - peptic ulcer disease
- 2. gastritis
- 3. GI bleed
- 4. GI perforation
Common GI AE of ibu?
have IBD S/S
What drug may be used to reduce NSAID GI upset in long-term NSAID therapy?
misoprostol/Cytotec r/t it increasing bicarbonate and mucous production in GI tract- inhibits gastric acid secretion
8 drug to drug interactions of ibu?
- 1. salicylates
- 2. aminoglycoside antibiotics
- 3. beta blockers
- 4. lithium
- 5. loop diuretics
- 6. selective serotonin reuptake inhibitors
- 7. antifungal agents
- 8. heparin
Who is at increased risk for GI bleeds with ibu?
ppl over 60
What type of pt may be on long-term NSAID therapy?
Imp consideration with ibu and pre-surgery pt/
must educate pt not take ibu close to surgery time (7 days?)
What type of drug is tylenol?
Action of acet?
inhibits synth of prostaglandins that serve as mediators of pain and fever but has no anti-inflammatory effects
2 uses for acet?
- 1. analgesia - mild to moderate
- 2. antipyretic
3 routes used for acet?
oral, rectal, and IV
When is IV acet used?
if oral or rectal cannot be tolerated and as adjunct to IV opiods
3 contraindications/cautious uses of acet?
- 1. hepatic disease
- 2. viral hepatitis
- 3. alcoholism
Serious AE of acet?
hepatic or renal toxicity
Drug to drug interactions with acet? (3)
- 1. warfarin
- 2. sulfinpyrazone/Anturane
- 3. hydantoins- dilantin, etc
What must be monitored when acet is taken with warfarin?
monitor PT & INR & S/S of bruising or bleeding
What education needs to be given to all pt about acet including those taken acet combination opiods?
acet is heptotoxic when take too much
Antidote for acet overdose?
Serotonin-selective drugs AKA?
Uses for triptans?
relieve pain and inflammation r/t migraine HA
first line Tx in migraine HA
3 types of triptans?
- 1. sumatriptan/Imitrex
- 2. rizatriptan/Maxalt
- 3. zolmitriptan/Zomig
Action of sumatriptan/Imitrex?
works as an agonist for 5HT 1d & 1B receptors on cranial arteries and veins
stim of these receptors = vasoconstrictions of BV in brain and decreses vascular inflammation
4 routes of admin for sumatriptan/Imitrex?
- 1. oral
- 2. intranasal
- 3. SQ
- 4. needleless injection - Sumavel DosePro
Pt taking sumatriptan/Imitrex are at increased risk for ____ & _____ r/t vasoconstriction of BV in brain?
stroke and MI
Onset of action for oral, intranasal, and SQ sumatriptan/Imitrex?
- oral - 1 h with complete relief up to 4 h
- intranasal 1 - 15 min
- SQ - 10 min with complete pain relief in 2 h
3 step admin?
6 contraindications/precautions of sumatriptan/Imitrex?
- 1. coronary artery disease
- 2. arteriosclerosis
- 3. ischemic cardiac disease
- 4. seizures
- 5. CVA, TIA, and intracranial bleeding
- 6. PVD - Raynaud disease
4 EX of ischemic cardiac disease that are contraindicated with sumatriptan/Imitrex?
- 1. uncontrolled HTN
- 2. angina pectoris
- 3. acute MI or Hx of MI
Common AE of sumatriptan/Imitrex?
- dizziness & vertigo
- tingling, warm, sensation
3 life-threatening AE of sumatriptan/Imitrex?
- 1. vasospasm effects leading to ischemia
- 2. MI
- 3. cerebrovascular disorders: stroke/ seizures, intracranial hemorrhage
What must be done prior to admin of sumatriptan/Imitrex?
must have a cardiac workup
3 assessments that should be done prior to sumatriptan/Imitrex admin?
- 1. Hx of CV or cerebrovascular disorder
- 2. obtain BP before and 1 h after admin
- 3. asses for S/S of cardiovascular event
disease-modifying antirheumatic drugs
3 DMARDS drugs?
- 1. methotrexate/Rheumatrex
- 2. adalimumab/Humira
- 3. hydroxycholoroquine/Plaquenil
Use for DMARDS?
arrest progression/induce remission of RA
DMARDS may be used as monotherapy or in combination with ______, _____ or _____.
- 1. glucocorticoids
- 2. NSAIDS
- 3. other DMARDS
autoimmune disease with systemic inflammtion of joints, tissues, and body organs & joint destruction
Action of methotrexate/Rheumatrex?
interferes with FA metabolism -> inhibits DNA synthesis and cell reproduction
Methotrexate/Rheumatrex may be used for what 2 things?
2 routes for methotrexate/Rheumatrex?
Contraindications & precautions with methotrexate/Rheumatrex?
- 1. immunosuppression
- 2. pre-existing blood dyscrasias
- 3. impaired bone marrow function
- 4. alcoholism
- 5. chronic liver disease
Most important thing to teach pt about methotrexate/Rheumatrex?
Common AE of methotrexate?
- 1. methotrexate fog - HA, fatigue, and feeling wiped out
- 2. photosensitivity
- 3. GI s/s
- 4. hematologic: anemia, leukopenia, and thrombocytopenia
2 Life threatening AE of methotrexate/Rheumatrex?
- 1. severe myelosuppression
- 2. pulmonary fibrosis or interstitial pneumonitis
Assessments to monitor with methotrexate?
- 1. CBC
- 2. Fe
- 3. breath sounds
- 4. fever
- 5. bleeding S/S
Assessments to make prior to admin of methotrexate/Rheumatrex? (4)
- 1. CBC & platelets
- 2. renal & hepatic function tests
- 3. hepatitis B & C serologies
- 4. chest x-ray
Methotrexate/Rheumatrex requires follow up q ___ to ___ wks with what 4 tests?
q 4 to 6 weeks
- 1. CBC
- 2. liver profile
- 3. albumin
- 4. creatinine
Why does albumin need to be monitored with methotrexate/Rheumatrex?
malnutrition increases risk of immunosuppression and blood dyscraisas
5 pt teachings for pt taking methotrexate/Rheumatrex?
- 1. limit intake of caffeine
- 2. wear sun protection
- 3. adequate nutrition
- 4. s/s of myelosuppression
- 5. take vitamin B/folic acid 1mg qd
Why do pt taking methotrexate/Rheumatrex not need to take any caffeine?
can decrease effectiveness of drug
S/S of myelosuppression to teach pt taking methotrexate/Rheumatrex?
- 1. sore throat
- 2. weakness
- 3. dry, nonproductive cough
- 4. nose bleed or bleeding gums
Why do pt taking methotrexate/Rheumatrex need to take folic acid supplement?
decreases the potential for AE
What is the biggest concern with a pt taking methotrexate/Rheumatrex?
risk for infection - if have fever need to take care of it immediately
What type of drug is etanercept/Enbrel?
tumor necrosis factor inhibitor
Action of etanercept/Enbrel?
binds to TNF & makes it inactive
Admin of etanercept/Enbrel?
(route and time)
SQ injection weekly
Uses for etanercept/Enbrel?
delay structural damage & s/s of RA
Contraindication with etanercept/Enbrel?
current active infection
Precaution with the use of etanercept/Enbrel?
can induce multiple sclerosis and optic neuritis
4 common AE of etanercept/Enbrel?
- 1. HA
- 2. upper resp tract infections
- 3. sinusitis
- 4. rhinitis
3 life threatening effects of etanercept/Enbrel?
- 1. severe infections
- 2. blood dyscrasias
- 3. induction of multiple sclerosis and optic neuritis
What is TNF?
tumor necrosis factor - mediator of inflammatory response that leads to release of destructive enzymes that destroy the joint in RA
2 things to teach pt taking etanercept/Enbrel?
- 1. no live virus vaccines: MMR, varicella
- 2. monitor for s/s of infection & call MD immediately
Important functions of the adrenal glands?
metabolism and F&E balances
2 things primarily secreted by the adrenal cortex?
glucocorticoids and mineralocorticoids
primary adrenal insufficiency esulting from the destruction of the adrenal cortex caused by infection or hemorrhage
Secondary adrenal insufficiency?
deficiency of cortisol secretion r/t insufficient secretion of ACTH by the ant pit
increased adrenocortical secretion of cortisol that causes chronic elevation in glucocortocoid and adrenal androgen hormones
2 primary glucocorticoids produced by the adrenal gland?
cortisol (hydrocortisone) & cortisone
What can abrupt disontinuation of a glucocoricoid following prolonged admin cause?
acute adrenal insufficiency
What type of drug is prednisone?
2 uses for prednisone?
anti-inflammatory & immunosuppressive effects
Precaution/contraindication for prednisone?
systemic fungal infections
What medical condition can further increase risk for fungal infection with prednisone?
DM r/t sugary blood
IV form of prednisone?
What med taken with prednisone can increase risk for fungal infection?
ABX because it increases fungus also
2 important considerations with prednisone use in diabetics?
- 1. can increase risk of fungal infections
- 2. prednisone raises BG - may need to increase insulin dose
AE of prednisone?
- 1. anxiety
- 2. mood swings
- 3. insomnia
- 4. HA
- 5. GI
- 6. menstrual irregularities
- 7. hyperglycemia
Imp consideration when giving prednisone to a pt experiencing dyspnea r/t airway issues/
pt is already anxious and prednisone increases anxiety
Most important considerations with prednisone?
- 1. suppesses immune system
- 2. raises BG
- 3. can decrease serum K+
2 interventions for fungal/yeast infections?
What is the best time to take daily or alternate-day doses of glucocorticoids?
early in the am
Prednisone effect on serum K+?
can decrease levels