Stage 3 drugs osce

Adalimumab(Humira)

• Name/therapy:Adalimumab(Humira)

• Drug class:Anti-TNF bioogic (monoclonal antibody)

• Mechanism of action: Binds to TNF-a → prevents inflammatory cascade → reduces immune-mediated inflammation

• Indications(NICE):- Rheumatoid arthiritis -Crohn’s disease -Ulcerative colitis -Psoriasis -Ankylosing spondylitis

• Contraindications:-Active infection (esp. TB) -Moderate-severe heart failure -Sepsis

• Counselling:-Screen for TB + hepatitis before starting -Report infection signs immediately -Avoid live vaccines -Injection technique education -store in fridge

• Interactions: -Increased infection risk with other immunosuppressants -Avoid live vaccines

Insulin

Name/therapy: Insulin
Drug class: Hormone replacement (antidiabetic)

Mechanism of action:
Promotes glucose uptake into cells → lowers blood glucose

Indications:

• Type 1 diabetes

• Type 2 diabetes (if uncontrolled)

• DKA (IV insulin)

Contraindications:

• Hypoglycaemia

Counselling:

• Recognise hypo symptoms (sweating, confusion)

• Rotate injection sites

• Monitor blood glucose regularly

• Carry glucose source

Interactions:

• Beta-blockers mask hypoglycaemia

• Steroids ↑ glucose → ↑ insulin requirement

3a. Metformin

Name/therapy: Metformin
Drug class: Biguanide

Mechanism of action:
↓ hepatic glucose production + ↑ insulin sensitivity

Indications (first-line NICE):

• Type 2 diabetes

Contraindications:

• eGFR <30

• DKA

• Severe dehydration

Counselling:

• Take with meals (reduce GI upset)

• Risk of lactic acidosis (rare)

• Stop during acute illness (“sick day rules”)

Interactions:

• Contrast media → ↑ lactic acidosis risk

3b. Gliclazide (Sulfonylurea)

Name/therapy: Gliclazide
Drug class: Sulfonylurea

Mechanism of action:
Stimulates pancreatic insulin release

Indications:

• Type 2 diabetes

Contraindications:

• Type 1 diabetes

• Severe renal/hepatic impairment

Counselling:

• Risk of hypoglycaemia

• Eat regularly

• Weight gain possible

Interactions:

• Alcohol ↑ hypoglycaemia risk

3c. Sitagliptin (Gliptin)

Name/therapy: Sitagliptin
Drug class: DPP-4 inhibitor

Mechanism of action:
↑ incretin hormones → ↑ insulin + ↓ glucagon

Indications:

• Type 2 diabetes

Contraindications:

• Caution in pancreatitis

Counselling:

• Generally well tolerated

• Report severe abdominal pain

Interactions:

• Low interaction risk

3d. Pioglitazone

Name/therapy: Pioglitazone
Drug class: Thiazolidinedione

Mechanism of action:
↑ insulin sensitivity in muscle/fat

Indications:

• Type 2 diabetes

Contraindications:

• Heart failure

• Bladder cancer history

Counselling:

• Weight gain + oedema

• Report haematuria

Interactions:

• ↑ fracture risk with steroids

3e. Dapagliflozin (SGLT2 inhibitor)

Name/therapy: Dapagliflozin
Drug class: SGLT2 inhibitor

Mechanism of action:
↑ urinary glucose excretion

Indications (NICE):

• Type 2 diabetes

• Heart failure

• CKD

Contraindications:

• DKA

• Severe renal impairment

Counselling:

• Risk of genital infections

• Stay hydrated

• Sick day rules (risk of DKA)

Interactions:

• Diuretics → dehydration risk

4a. Sodium Valproate

Name/therapy: Sodium valproate
Drug class: Antiepileptic

Mechanism of action:
↑ GABA levels → stabilises neuronal activity

Indications:

• Generalised seizures

• Bipolar disorder

Contraindications (VERY IMPORTANT NICE):

• Pregnancy (unless strict PPP followed)

Counselling:

• Major teratogenic risk ⚠

• Use contraception

• Monitor liver function

Interactions:

• ↑ levels of lamotrigine

4b. Phenytoin

Name/therapy: Phenytoin
Drug class: Antiepileptic (Na+ channel blocker)

Mechanism of action:
Stabilises neuronal membranes

Indications:

• Tonic-clonic seizures

Contraindications:

• Sinus bradycardia (IV use caution)

Counselling:

• Gingival hyperplasia (oral hygiene!)

• Avoid abrupt withdrawal

Interactions:

• Strong enzyme inducer → ↓ OCP effectiveness

4c. Lamotrigine

Name/therapy: Lamotrigine
Drug class: Antiepileptic

Mechanism of action:
Blocks sodium channels → ↓ glutamate release

Indications:

• Focal seizures

• Bipolar depression

Contraindications:

• Hypersensitivity

Counselling:

• Risk of Stevens–Johnson syndrome ⚠

• Start low, go slow

Interactions:

• Valproate ↑ lamotrigine levels

5. Clozapine

Name/therapy: Clozapine
Drug class: Atypical antipsychotic

Mechanism of action:
Blocks dopamine (D4>D2) + serotonin receptors

Indications (NICE):

• Treatment-resistant schizophrenia

Contraindications:

• History of agranulocytosis

• Uncontrolled epilepsy

Counselling:

• Regular blood monitoring (ANC/WBC) ⚠

• Report infection signs urgently

• Causes sedation, weight gain

Interactions:

• Smoking ↓ levels (CYP1A2 induction)

• ↑ levels with infection

6. Contraceptives a) Progesterone-only pill (Desogestrel)

Name/therapy: Desogestrel (POP)
Drug class: Progestogen-only contraceptive

Mechanism of action:
Inhibits ovulation + thickens cervical mucus

Indications:

• Contraception (esp. if oestrogen contraindicated)

Contraindications:

• Active breast cancer

Counselling:

• Take at same time daily

• Missed pill rules important

• Irregular bleeding common

Interactions:

• Enzyme inducers ↓ effectiveness

b) Combined oral contraceptive (Microgynon)

Name/therapy: Ethinylestradiol + levonorgestrel (Microgynon)
Drug class: Combined hormonal contraceptive

Mechanism of action:
Inhibits ovulation

Indications:

• Contraception

• Menstrual regulation

Contraindications:

• VTE history ⚠

• Migraine with aura

• Smoking >35 years

Counselling:

• VTE risk signs (leg pain, SOB)

• Missed pill guidance

• Take daily

Interactions:

• Enzyme inducers (e.g., phenytoin) ↓ efficacy

7. Donepezil

Name/therapy: Donepezil
Drug class: Acetylcholinesterase inhibitor

Mechanism of action:
↑ acetylcholine in brain

Indications (NICE):

• Mild–moderate Alzheimer’s disease

Contraindications:

• Caution in bradycardia

Counselling:

• GI side effects common

• May cause sleep disturbance

Interactions:

• Anticholinergics ↓ effect

8. Emergency Hormonal Contraception a) Levonorgestrel

Name/therapy: Levonorgestrel
Drug class: Progestogen

Mechanism of action:
Delays ovulation

Indications:

• Emergency contraception (within 72h)

Contraindications:

• Severe liver disease

Counselling:

• Take ASAP

• Vomiting within 3h → repeat dose

Interactions:

• Enzyme inducers ↓ efficacy

8. Emergency Hormonal Contraception b) Ulipristal

Name/therapy: Ulipristal
Drug class: Progesterone receptor modulator

Mechanism of action:
Delays ovulation

Indications:

• Emergency contraception (up to 120h)

Contraindications:

• Severe asthma on steroids

Counselling:

• Avoid hormonal contraception for 5 days after

• Breastfeeding interruption required

Interactions:

• Enzyme inducers ↓ effectiveness

9. Fluconazole

Name/therapy: Fluconazole
Drug class: Azole antifungal

Mechanism of action:
Inhibits ergosterol synthesis (fungal cell membrane)

Indications:

• Candida infections

Contraindications:

• QT prolongation risk

Counselling:

• Usually single dose for thrush

• Report palpitations

Interactions:

• CYP inhibitor → ↑ warfarin, statins

10. Hormone Replacement Therapy (HRT)

Name/therapy: Oestrogen ± progestogen
Drug class: Hormone replacement

Mechanism of action:
Replaces declining oestrogen

Indications (NICE):

• Menopausal symptoms

Contraindications:

• Breast cancer history

• VTE history

Counselling:

• Risks: VTE, breast cancer

• Benefits: symptom relief, bone protection

Interactions:

• Enzyme inducers ↓ effect

11. Leflunomide / Hydroxychloroquine a) Leflunomide

Name/therapy: Leflunomide
Drug class: DMARD

Mechanism of action:
Inhibits pyrimidine synthesis → ↓ lymphocyte proliferation

Indications:

• Rheumatoid arthritis

Contraindications:

• Pregnancy ⚠

Counselling:

• Long half-life

• Monitor LFTs + BP

Interactions:

• Hepatotoxic drugs ↑ risk

11. Leflunomide / Hydroxychloroquine b) Hydroxychloroquine

Name/therapy: Hydroxychloroquine
Drug class: DMARD

Mechanism of action:
Immunomodulatory (exact unclear)

Indications:

• RA

• SLE

Contraindications:

• Retinopathy

Counselling:

• Regular eye exams ⚠

Interactions:

• QT prolonging drugs

12. Levothyroxine

Name/therapy: Levothyroxine
Drug class: Thyroid hormone (T4)

Mechanism of action:
Replaces deficient thyroid hormone

Indications:

• Hypothyroidism

Contraindications:

• Untreated thyrotoxicosis

Counselling:

• Take on empty stomach

• Long-term therapy

• Monitor TSH

Interactions:

• Iron/calcium ↓ absorption

13. Lithium

Name/therapy: Lithium
Drug class: Mood stabiliser

Mechanism of action:
Alters neurotransmission (exact mechanism unclear)

Indications (NICE):

• Bipolar disorder (mania + prophylaxis)

Contraindications:

• Severe renal impairment

• Untreated hypothyroidism

Counselling:

• Narrow therapeutic index ⚠

• Regular blood monitoring (levels, TFTs, U&Es)

• Maintain fluid + salt intake

• Toxicity signs: tremor, confusion, vomiting

Interactions:

• NSAIDs, ACE inhibitors, diuretics ↑ lithium levels ⚠

14. Memantine

Name/therapy: Memantine
Drug class: NMDA receptor antagonist

Mechanism of action:
Reduces glutamate excitotoxicity

Indications (NICE):

• Moderate–severe Alzheimer’s disease

Contraindications:

• Caution in epilepsy

Counselling:

• Dizziness possible

• Generally well tolerated

Interactions:

• Other NMDA antagonists

15. Methotrexate

Name/therapy: Methotrexate
Drug class: DMARD / antimetabolite

Mechanism of action:
Inhibits folate metabolism → ↓ DNA synthesis

Indications:

• Rheumatoid arthritis

• Psoriasis

Contraindications:

• Pregnancy ⚠

• Liver disease

Counselling:

• ONCE WEEKLY dosing ⚠ (very important)

• Take folic acid

• Monitor FBC + LFTs

• Report mouth ulcers, infection

Interactions:

• Trimethoprim ↑ toxicity ⚠

16. Morphine

Name/therapy: Morphine
Drug class: Opioid analgesic

Mechanism of action:
μ-opioid receptor agonist → pain relief

Indications:

• Severe pain

Contraindications:

• Respiratory depression

Counselling:

• Constipation (laxative needed)

• Drowsiness

• Addiction risk

Interactions:

• Other CNS depressants ↑ sedation

17. SSRIs (Sertraline, Fluoxetine)

Name/therapy: SSRIs (e.g., sertraline, fluoxetine)
Drug class: Antidepressants

Mechanism of action:
Inhibit serotonin reuptake → ↑ serotonin

Indications (NICE):

• Depression

• Anxiety disorders

Contraindications:

• Concomitant MAOIs

Counselling:

• Takes 2–4 weeks to work

• Initial anxiety may worsen

• Risk of serotonin syndrome

Interactions:

• MAOIs → serotonin syndrome ⚠

Anti-Parkinson’s Medications a) Co-careldopa / Co-beneldopa

Name/therapy: Levodopa + dopa-decarboxylase inhibitor
Drug class: Dopaminergic

Mechanism of action:
Levodopa → dopamine in brain

Indications:

• Parkinson’s disease

Contraindications:

• Narrow-angle glaucoma

Counselling:

• Wearing-off effect

• Dyskinesias

Interactions:

• Antipsychotics ↓ effect

18. Anti-Parkinson’s Medications b) Pramipexole

Name/therapy: Pramipexole
Drug class: Dopamine agonist

Mechanism of action:
Stimulates dopamine receptors

Indications:

• Parkinson’s disease

Contraindications:

• Psychotic disorders

Counselling:

• Impulse control disorders ⚠

• Sudden sleep episodes

Interactions:

• Additive CNS effects

19. Prednisolone

Name/therapy: Prednisolone
Drug class: Corticosteroid

Mechanism of action:
Suppresses inflammation + immune response

Indications:

• Asthma

• Autoimmune diseases

Contraindications:

• Untreated infections

Counselling:

• Take in morning

• Do not stop abruptly ⚠

• Long-term: osteoporosis risk

Interactions:

• NSAIDs ↑ GI bleeding risk

20. Quetiapine

Name/therapy: Quetiapine
Drug class: Atypical antipsychotic

Mechanism of action:
Blocks dopamine + serotonin receptors

Indications:

• Schizophrenia

• Bipolar disorder

Contraindications:

• Caution in cardiovascular disease

Counselling:

• Sedation

• Weight gain

Interactions:

• CYP3A4 inhibitors ↑ levels

21. Sulfasalazine

Name/therapy: Sulfasalazine
Drug class: DMARD / anti-inflammatory

Mechanism of action:
Modulates inflammatory mediators

Indications:

• Rheumatoid arthritis

• Ulcerative colitis

Contraindications:

• Sulfa allergy

Counselling:

• Orange urine/tears (harmless)

• Monitor FBC + LFTs

Interactions:

• ↑ risk of myelosuppression

22. Sildenafil

Name/therapy: Sildenafil
Drug class: PDE-5 inhibitor

Mechanism of action:
↑ cGMP → vasodilation in corpus cavernosum

Indications:

• Erectile dysfunction

Contraindications:

• Nitrates ⚠ (severe hypotension)

Counselling:

• Take before sexual activity

• Avoid nitrates

Interactions:

• Nitrates → life-threatening hypotension ⚠