Week 7 - Drug Reactions Flashcards
Who is most at risk of developing a cutaneous drug reaction?
- The Eldery
- Polypharmacy patients
- HIV
Which drugs are most likely to cause cutaneous reactions?
- Antibiotics
- Analgesics
- NSAIDS
- Thiazide diuretics
- Anticonvulsants
What are the two types of adverse drug reactions?
- Immunological (Drug Allergy)
- Non-Immunological (Drug Intolerance) -90% of reactions are this.
What are the most common types of drug eruptions?
- Pruritus
- Maculopapular Exanthems
- Urticaria
- Angio-Oedema
- Photoallergic reactions
- Fixed Drug Reactions
When do drug reactions usually occur?
7-10 days
How can you tell the difference between a viral rash and a drug induced rash?
- Viral rashes start on the face and acral sites then spread to the trunk.
- Viral rashes have associated symptoms like sore throat, GI symptoms, Cough, Conjunctivitis.
- Drug induced reactions are usually itchy.
What are the drugs associated with exanthem reactions?
- Ampicillin and penicillin
- Carbamazepine
- Sulphonamides
- Phenytoin
- NSAIDs
- Allopurinol
What type of drug reaction is this?
Morbilliform Exanthem (aka maculopapular reaction) - the most common
What is the second most common type of reaction?
Urticaria/anaphylaxis
What drugs are associated with urticarial/anaphylactic reactions?
- Aspirin
- NSAIDS
- Beta lactam antibiotics, including penicillins
What drugs can cause pruritus?
- Opioids
- Statins
- ACE-inhibitors
- NSAIDS
What type of drug reaction is this?
Symmetrical drug-related intertriginous and flexural exanthem
What drugs are associated with symmeterical intertriginous and flexural exanthem?
- Penicillins
- Cephalosporins
- Erythromycin
- NSAIDS
In what 2 patterns can lichenoid drug eruptions occur?
Lichen plaus or Lupus
How long after exposure do Lichenoid drug eruptions usually occur?
Months
What drugs are commonly associated with drug-induced lichen planus?
- Antimalarials
- Gold
- NSAIDS
- Mercury amalgam
- Penicillamine
- Thiazide diuretics
What drugs are commonly associated with drug-induced Lupus Erythematosus?
- ACE-inhibitors
- Beta blockers
- Calcium channel blockers (eg. diltiazem)
- Statins
- Thiazide diuretics
What is this?
A Drug-Induced Lichenoid reaction
What is a fixed drug eruption?
A recurrent well-defined lesion that occurs in the same place each time the drug is taken.Typically causes an oval plaque that starts red and oedmatous and evolves to become dusky, violaceous and occasionally bullous. Onset 30 minutes to 8 hours after exposure.
What drugs cause a fixed drug eruption?
- NSAIDs
- Paracetamol
- Tetracyclines
- Co-trimoxazole
What drugs are responsible for a drug-induced photosensitivity reaction?
- NSAIDS
- Tetracyclines
- Isotretinoin
- Statins
- Frusemide
- Thiazide diuretics
What drugs are responsibl for Drug-Induced Acneform Eruptions?
- Corticosteroids
- Androgens and anabolic steroids
- Hormonal contraceptives
- Lithium
- Phenytoin
- Valproate
- Ciclosporin
When do Drug-induced acneform eruptions usually occur?
1-2 weeks after taking the drug
How can you tell if an acneform eruption is different from acne?
Acneform eruptions often lack comedonees or cysts.
What are the commonest causes for EM?
- Herpes simplex (90%)
- Mycoplasma Pneumonia
- Prior EM
What are some other infections that cause Erythema Multiforme (EM)?
- CMV infection
- EBV infection
- HIV infection
- Lymphoma
- Histoplasmosis
- Hepatitis B vaccine
- Syphilis
- Orf virus
What are some medications that cuase Erytheme Multiforme?
- NSAIDS
- Penicillins
- Sulphonamides
- Barbiturates
- Anticonvulsants
- Phenothiazines
What is the typical disease course for EM?
- Acroal targetoid lesions - Bull’s eye lesions start at the beginning
- An eruption over the rest of the body occurs
- Resolves in 2-3 weeks.
What is the treatment for Erythema Multiforme?
- Symptomatic relief.
- Opthalmological advise if eye involvement.
- Topical steroids
- Oral aciclovir if severe (EM Major)
- Oral steroids is controversial but may shorten disease duration.
What is DRESS?
Drug Rash with Eosinophilia & Systemic Symptoms
- Fever, lymphadenopathy and a rash.
- Facial oedema commonlyoccurs.
- Eosinophila & abnormal LFTs.
- Occurs 1-6 weeks after drug ingested.
What drugs most commonly cause DRESS?
- Allopurinol
- Antiepileptics
- Antibiotics including minocycline, amoxicillin
- Frusemide
- Omeprazole
- Ibuprofen
What is AGEP?
Acute Generalised Exanthematous Putulosis
- The rapid development of sterile pustules in the flexural areas.
- Usually start 2-5 days after starting the drug
What drugs cause AGEP?
- Amoxicillin
- Quinolones
- Chloroquine and hydroxychloroquine
- Sulphonamides
- Terbinafine
A person has taken Cetuximab, what is this called?
Papulopustular eruption secondary to Epidermal Growth Factor receptor inhibition.
- 90% will develop this on this drug.
- 7-10 days after initiation.
A person has started chemotherapy. What is this?
Palmoplantar erythrodysaesthesia secondary to chemotherapy
- Acral erythema starts 1day to 3 weeks after starting chemotherapy.
- Tinglingor burning precedes the reaction.
- Often with Doxorubicin
What are the 2 changes in stem cell transplantation?
- Acute GVHD (Graft vs Host disease) - within 100 days of graft.
- Usually a macular erythematous eruption with abnormal LFTs andGI symptoms.
- Chronic GVHD (seen below) After 100 days.
- sclerodermatous or lichen planus on the skin.
What drug causes this?
Bleomycin
What can Nicorandil cause?
Painful perineal ulcers
What percentage of inpatients will have a drug reaction?
10-20%
What class of drug commonly causees cutaneous drug reactions?
Anticonvulsants
What sensory ogan is commonly affected in TEN?
The eyes
What are the common drugs reaction patterns?
- Exanthems
- Pruritus
- Fixed Drug Eruptions
- Urticaria/Anaphylaxis
- Fixed flexural and intertigous exanthems
- Lichenoid
- Acneform
If someone has a fixed drug reaction, would the reactions occur at the same site everytime the drug is taken?
Yes
What is a common feature of a fixed drug reaction?
A central blister
In hypersensitivity syndrome, what dermatitis is common?
An exfoliative dermatitis.
What drugs are a common cause of photosensitive drug reactions?
NSAIDs
What reaction can Anti-convulsants cause?
An acne-type lesion on the face.
