Drugs in inflammatory diseases - Methotrexate

Learning objectives By the end of this screencast, you should be able to: • Describe the therapeutics of key medicines involved in the management of immune diseases 2

State three conditions low dose MTX ?

Rheumatoid arthritis

psoriasis

inflammatory bowel disease

What is high dose MTX used for?

Cancer chemotherapy

State the range of bioavailability of MTX ?

6-90%

Prior to proper administration, how much will be given as a test dose?

2.5 mg

a single one off dose

What is the purpose of the test dose?

to rule out idiosyncratic effects

How many times should low dose MTX be administered?

ONCE A WEEK , ON THE SAME DAY EACH WEEK

How should instructions for MTX administration be written?

In full

and clearly written

Can you prescribe different doses of MTX to make up to a specific dose?

No the same dose(2.5mg) should be presribed to make up the final dose

How often should MTX instructions be reiterated?

At every review,

anytime you speak to the patient

What must each patient that takes MTX carry on them?

An alert card

contains drug info and side effects

How long may it take for MTX to start working?

6 weeks

And in about how many weeks can you begin to see MTX’s full effect?

12 weeks

By how much can you incr the MTX ?

2.5- 5mg every 1-3 week s

In about how long do we aim to reach optimal dose?

4-6 weeks

Name 2 baseline assements that will be done for starting MTX therapy?

FBC - full blood count

LFT - liver function test

Why is a FBC conducted?

To monitor and assess bone marrow function

Name 2 baseline assements that will be done for starting MTX therapy? U, R

Urea & Electrolytes (U&E )

Name 2 monitoring parameters observed in a renal function test?

Creatine

Estimated glomerular filtration rate

Name the last monitoring parameters observed in a renal function test?

eGFR

Name 2 other baseline assements that will be done for starting MTX therapy?

Renal function

Chest x-ray

Why is a chest x-ray conducted?

To monitor any signs of pulmonary toxicity

Until the therapy is stabilised, how often do you need to monitor MTX therapy?

every 1-2 weeks

One stabilised how often must MTX therapy be monitored?

every 2-3 months

Are the monitoring req the same for each condition MTX is used for?

no

State 3 self monitoring SE patients need to be aware of when on MTX - sign of infection?S , B&B

Sore throath

Brusing and bleeding(possible blood disorders)

State 2 SE that can suggest liver toxicity?

Nausea and Vomiting

State 2 SE that can suggest liver toxicity? AD, DU

Abdominal discomfort

and

dark urine

State a respiratory self monitoring SE patients need to be aware of when on MTX

Shortness of breath - SOB

What does DMARD stand for?

disease-modifying antirheumatic drug

State an importance of folic acid?

helps your body make new cells such as red blood cells

What does Methotraxate do to folic acid?

blocks some of the actions of folic acid,

leading to side effects such as abdominal pain.

What is the usual prescribing dose for co-prescribed folic acid?

5 mg once daily.

How many days should you take the co-prescribed folic acid?

1 to 6 days a week

except for the MTX day

State two benefits of taking the folic acid?

reduce risk of hepatoxicity

and

GI side effects

State three things elderl patients may be more prone to

Less natural folate production

Renal

hepatic imparement

How many key side effects are stated in your lecture slides?

5 side effects.

State three key side effects? B,G T,L T

Bone marrow suppression

GI toxicity

Liver toxicity

State 2 key side effects? P T , S R

Pulmonary toxicity

skin reactions

State 2 oral symptoms of using MTX

Mucositosis

and

oral ulceration

State 3 repiratory symptoms of using MTX

Dry cough, brethlessness ,—fever —

State two sign of liver toxicity when taking MTX?

Yellow eyes ,

persistent nausea and vomiting

Is MTX recommended when someone is having an active infection?

No

MTX further reduces immune response

State two types of impairment were MTX is contraindicated?

Severe renal impairment

Hepatic impairemnt

In which kind of supression and state is MTX contraidicated ?

Bone marrow supression

and

immunodeficiency

Is MTX recommended in pregnancy and breast feeding?

No

Advice for conception on MTX?(both men and women)

Do not attempt during up to 6 months after treatment

What should men and women of reproductive age use whiles on MTX?why?

contraceptive methods

MTX can cause teratogenic effects

What should patients know about N&V side effect?

It is self-limiting

If N&V is not improving state 2 options for treatment?

-increase folic acid uptake - eg to other days of the week

-use antiemetics

What test should a patient do if they experience ulcers and sore mouth?(sign of toxicity)

Blood test

If you have not gotten this disease before consult with the doc before using MTX?

Chicken pox

Before which procedure is MTX usually stopped?

Surgery

as it increases risk of infection

Name 2 of the key cautions in prescribing low dose MTX ? S and R

Surgery

Renal imparement

Name 2 of the key cautions in prescribing low dose MTX ? D and A

Diarrhoea

Ascites (fluid build up)

Name a key caution in prescribing low dose MTX ? P

Peptic ulcer

Name 2 side effects some may medicines cause that we need to be wary off?(renal impact)

Dehydration

Bone marrow suppression

Are you advised to supply more than the required amount of low dose MTX?

No

Only the required amount

What instruction would you give to a patient that has missed a dose of MTX?

Can be taken within next 2 days

Must the patient switch the day of the week if they forget a dose?

after the missed is taken

The day of the week must not be changed

What is the number 1 contraindication for all medicines?

Allergy

Why do past figures show so many problems with patient’s experience with low dose MTX?

Taking it incorectly leading to toxicity and serious adverse reactions

When taking low dose MTX what may happen to psoriasis lesions?

They may be aggrevated by UV radiation (photosensitivity)

Name 2 anti-folates MTX may have an interaction with?

Co-trimoxazole, trimetoprim

What may be increased when MTX is taken at the same time as an anti-folate?

Toxicity

When may a patient take an NSAID whiles taking MTX?

Under the direction of a prescriber

Why should patients on low dose MTX avoid live vaccine?

compromised immune system = sub-optimal response to the vaccine

Name an immunosupressant that should be avoided whiles taking MTX?

Ciclosporin

State 2 recommended vaccines for those on low dose MTX?

Pneumococcal

Influenza

A patient on MTX should inform all…

Health care professionals they come in contact with about their MTX usage

Suggest a place a patient could put their MTX card? maybe monitoring booklet too

Purse/Wallet

Why must patients aim to consume less than the recommended daily amounts of alcohol?

To reduce the risk of liver toxicity

If in need of pain relief…

ask a healthcare professional !