High Risk Drugs COPY Flashcards
What is Carbimazole used for?
Hyperthyroidism
Report any sore throat, ulcers, fever, malaise, bleeding with Carbimazole
What is the difference between:
- Agranulocytosis*
- Thrombocytopenia*
- Blood Dyscrasias*
- Agranulocytosis:* WBC’s go down; sore throat, fever, malaise all symptoms
- Thrombocytopenia:* Platelets go down: blood very thin: unexplained bleeding/ bruising. Can be from Heparins
- Blood Dyscrasias:* Entire blood profile goes down; symptoms of both of the above, this is why we report both sets of symptoms with some drugs
What is the loading dose of Amiodarone?
200mg TDS for 7 days
200mg BD for 7 days
Then 200mg OD from there on (maintenance)
Why load? Long half life (50 days) means it would take ages to reach therapeutic levels. Also means interactions can still occur months after stopping.
Symptoms of Aspirin Overdose (5)
Tinnitus
Hyperventilation
Deafness
Vasodilation
Sweating
Why is rifampicin considered High Risk do you think?
(Rifampicin is one of the TB drugs)
Many interactions- as it is an enzyme Inducer, it induces ALL of the CYP enzymes: decreases efficacy of COC’s
HEPATOTOXIC: Monitor LFTs, counsel on liver toxicity signs, stop if:
Persistent Nausea
Vomiting
Malaise
Jaundice
Also colours urine/ body fluids/ soft contact lenses red/ orange
What monitoring is needed with Rifampicin?
LFT’s before starting- continue to monitor if on prolonged therapy
Renal function before starting
FBC if on prolonged therapy
Which class of antibiotics do we need to use with caution in EPILEPTICS?
Quinolones-
Ciprofloxacin, Levofloxacin
These lower seizure threshold!
Particularly if used with theophylline
Why do we need to check albumin levels with warfarin?
Warfarin is highly protein bound to albumin- if this is low there may be issues transporting it round the body
need to monitor both renal and liver function with warfarin
People stable on warfarin- how often is INR checked?
Every 3 months
Unless changes in clinical status occur e.g. diarrhoea and vomitting
What (quite unpleasant) side effects are associated with Amiodarone use, what signs should patients look out for? (7)
Nausea and vomitting and taste disurbance
Thyroid function- Hypo and Hyperthyroidism through action of IODINE in the drug
Phototoxic skin reactions: burning sensation, erythema, slate grey skin discolouration
Pulmonary toxicity- persisitent SOB/ Cough
Tremor- peripheral neuropathy- numbness in hands and feet
Corneal microdepositis in eyes- dazzled by headlights- common SE: this is reversible once drug stopped
Liver toxicity: Jaundice
What 5 things need monitoring at baseline with Amiodarone?
LFT’s- Hepatotoxicity a risk
THYROID FUNCTION- hyper/hypothyroidism
Serum Potassium!!!! before starting
Chest X-ray- pulmonary toxicity
ECG with IV use
LFT’s and TFT’s need monitoring after 6 months too!
What is Amiodarone used for?
Treatment of
Both supraventricular and ventricular Arrhythmias
Ventricular fibrilation, ventricular tachycardia
Usually used when other drugs failed as quite a nasty drug
Rhythm control as part of pharmacological cardioversion in AF
Methotrexate inhibits dihydrofolate reductase and therefore reduces folate in the body. What drug has to be given with methotrexate as supplementation to prevent its nasty side effects, and when?
For prevention of methotrexate induced horrible side effects in Chron’s/ RA:
Folic acid 5mg ONCE WEEKLY- dose to be taken on a DIFFERENT DAY to methotrexate
Methotrexate may lead to blood disorders (most significantly neutropenia and increased infection risk) through BONE MARROW SUPPRESSION. Its anti- folate propertied may explain how it suppresses bone marrow…
Bone marrow is where the body creates new cells. Cell division requires folate in order to occur.
Since folate deficiency limits cell division, erythropoiesis, production of red blood cells, WBC, neutrophils etc is suppressed in the bone marrow when methotrexate is taken as it is anti- folate. This is the same story as with Trimethoprim/ Co- trimoxazole and Phenytoin as these are also anti-folate- Avoid use together!
Production of RBC’s being hindered also leads to megaloblastic anemia, which is characterized by large immature red blood cells that cannot divide.
What monitoring does Methotrexate require?
Renal function
LFT’s
FBC (due to blood disorder risk)
These should be 1-2 weekly until dose stabilised then 2-3 monthly thereafter
Exclude pregnancy- pregnancy test before starting?
Avoid in hepatic impairment and reduce dose in renal impairment unless severe- then avoid.
What is Methotrexate used for?
Main use in:
Rhumatoid Arthritis
Severe Chron’s (Inflammatory Bowel Disease)
Severe Psoriasis
It is cytotoxic- stops cell division- part of chemotherapy
What are the Methotrexate warning signs
Blood disorder: Bone marrow suppression- sore throat, ulcers, fever, rash
Liver toxicity- N&V, abdominal pain, dark urine, Jaundice
Gastro-intestinal toxcitiy: stomatitis, GI upset (sore mouth first symptom)
Pulmonary Toxicity- persistent SOB, cough
PREGNANCY & Breastfeeding- its anti-folate so avoid!!- contraception needed during treatment and for 3 months after stopping
WITHDRAW TREATMENT IF ANY OF THESE OCCUR
What OTC med’s can increase the risk of Methotrexate toxicity?
NSAIDS/ ASPIRIN !!
Reduce methotrexate excretion in kidney
As do penicillins!
A patient comes in complaining of mouth sores, they think it may be cold sores. After further questioning you find out they are on Methotrexate. What do you do?
Advise they seek medical attention ASAP
Mouth sores may be a sign of stomatitis (inflammation of mouth) which is the first sign of Gastro-intestinal toxicity associated with Methotrexate!
A patient asks for some Lozenges as they are experiencing a very sore throat. You find out they are on Methotrexate. What do you do?
Seek medical attention ASAP
Sore throat is most common side of blood disorders with Methotrexate
Patients can sometimes overdose on Methotrexate as they get confused that it is Just once weekly dosing. What are the symptoms? what is methotrexate toxicity treated with?
Renal impairment
Liver impairment
Headache, seizures, coma
Treatment: FOLINIC ACID- rescues normal cells from methotrexate effects
What happens when Baclofen (used for pain of muscle spasms in palliative care/ trauma) is suddenly withdrawn? What if it is given with ACE inhibitors or Beta blockers?
Suddenly withdrawn: hyperactivity, hyperthermia, hallucinations, convulsions
Enhanced Hypotensive effects with ACEi/ Beta blockers
Which NOAC is contra-indicated in patients with a Prosthetic valve?
DABIGATRAN
ORLISTAT (Alli)
What needs monitoring with Vancomycin (4)?
Full blood count: can cause both LOW PLATELETS and LOW NEUTROPHILS (Neutropenia)
Renal function- Nephrotoxic- Urinalysis, CrCl used for dosing
Hearing function in the elderly
Plasma concentration
What needs monitoring with Gentamicin?
Renal function
Hearing function
Plasma concentration
NB: differs to vancomycin as do not need to monitor FBC- does not cause neutropenia/ low platelets
What type of vaccines are Ciclosporin and Tacrolimus Contra-indicated with?
Live vaccines
Live vaccines can, in some situations, cause severe or fatal infections in immunosuppressed individuals due to extensive replication of the vaccine strain that the immune system cannot fight off.
Same goes with high dose corticosteroids: these can suppress the immune system so avoid live vaccines
