Medicines 40 Flashcards
What dietary or medicinal precautions should be taken with ciprofloxacin?
Avoid milk, indigestion remedies, or medicines containing iron or zinc for 2 hours before and after taking ciprofloxacin, as they can reduce its absorption.
What is important to know about phenytoin’s pharmacokinetics?
Phenytoin is ~90% plasma protein bound and metabolized in the liver.
At low concentrations, it follows first-order kinetics (elimination proportional to concentration).
At therapeutic levels, metabolism becomes saturated, leading to zero-order kinetics — small dose increases can cause large rises in free phenytoin levels.
What are the signs of lithium intoxication?
Blurred vision
Resting tremor
Muscular weakness
Confusion, ataxia, coarse tremor, drowsiness, and in severe cases: seizures, coma, and renal failure.
Remember:
Mnemonic: “LiTHIUM”
Each letter helps you remember a key symptom:
L – Lethargy / Light-headedness
T – Tremor (coarse, resting)
H – Hyperreflexia / Hypotonia (muscle weakness)
I – Impaired vision (blurred vision)
U – Unsteady gait (ataxia)
M – Mental changes (confusion, drowsiness, coma)
Specifically, What blood monitoring is required when initiating and continuing clozapine therapy, and what are the criteria for discontinuation due to neutropenia?
🔍 Before starting:
✔️ WCC & differential must be normal
📅 Monitoring schedule:
🔸 Weekly for first 18 weeks
🔸 Then every 2 weeks
🔸 After 1 year stable: every 4 weeks
🔸 Continue for 4 weeks after stopping
🛑 Discontinue & refer to haematologist if:
⚠️ WCC < 3000/mm³
⚠️ Neutrophils < 1500/mm³
What is Vigabatrin and …
What are the key safety concerns with vigabatrin and how should patients be monitored?
Vigabatrin is an antiepileptic (anticonvulsant) medicine used primarily for:
Infantile spasms (West syndrome) – particularly in children under 2 years old
Refractory focal seizures (partial seizures) – only when other treatments have failed or aren’t suitable
🧨 Seizure Exacerbation:
Vigabatrin may worsen:
❌ Absence seizures
❌ Myoclonic seizures (e.g., juvenile myoclonic epilepsy)
❌ Tonic/atonic seizures
❌ Dravet & Lennox-Gastaut syndromes
❌ Myoclonic-atonic seizures
👁️ Visual Field Defects:
Risk may appear from 1 month to several years after starting
Often irreversible, may worsen even after stopping
⚠️ Test visual fields:
🔍 Before starting
🔁 Every 6 months during treatment
🗣️ Warn patients & carers to report new visual symptoms
📞 Urgent ophthalmology referral if symptoms appear
💊 Consider gradual withdrawal if issues arise
What important visual side effect is associated with linezolid, and what advice should be given to patients?
🔸 Linezolid can cause severe optic neuropathy.
🔸 Patients should be advised to report any changes in eyesight, such as:
Changes in visual acuity
Changes in colour vision
Blurred vision
Any visual field defects
🔸 Prompt evaluation and referral to an ophthalmologist is recommended if symptoms occur.
🔸 If linezolid is taken for more than 28 days, regular visual monitoring is advised.
What is Aztreonam?
A monobactam antibiotic
Active against aerobic Gram-negative bacteria (including Pseudomonas aeruginosa)
No activity against Gram-positive bacteria or anaerobes
What can vitamin K be used for in babies?
injection at birth to prevent serious bleeding, including intracranial bleeding.
What is Oxytocin?
A hormone and medication
Produced naturally by the pituitary gland
Synthetic form used in medical settings
🔑 Key Uses of Oxytocin:
Induction of labour:
Stimulates uterine contractions to initiate or accelerate labour
Administered via IV infusion in controlled doses
Postpartum haemorrhage prevention:
Administered after delivery to reduce bleeding by promoting uterine contraction
What is the treatment for spacsticity symptoms in MS?
💊 First-Line Treatment:
Baclofen is often recommended first-line for spasticity management.
Consider comorbidities, drug interactions, contraindications, and patient preference when choosing treatment.
💊 Second-Line Option:
Gabapentin (off-label use as of Aug 2022) can be used if baclofen is not tolerated or ineffective.
What is the treatment for relapse in MS?
💊 First-line Treatment:
Oral methylprednisolone 500 mg once daily for 5 days
(Start as early as possible, within 14 days of symptom onset)
⚠️ Do NOT:
Use lower doses
Provide steroids in advance for self-use
💡 Key Points:
Not all relapses need steroids (e.g., mild relapse)
Discuss risks and benefits:
Reduces relapse duration (~13 days)
May reduce severity
Potential side effects: mood changes, agitation, confusion, hyperglycaemia
What is key to remember about timolol eye drops ?
💊 Drug Class:
Beta-blocker (topical ophthalmic)
📌 Systemic Absorption:
Systemically absorbed despite topical use
Can cause systemic beta-blocker effects (e.g. ↓ HR, ↓ BP, bronchospasm)
🫀 Cardiovascular Risks:
Use caution in:
Coronary heart disease
Prinzmetal’s angina
Cardiac failure
First-degree heart block
May cause bradycardia, hypotension, heart failure exacerbation
Monitor pulse rate and watch for signs of heart failure
🧊 Vascular Concerns:
Use with caution in severe peripheral circulatory disorders (e.g. Raynaud’s)
🫁 Respiratory Risks:
Contraindicated in asthma ❌ (risk of bronchospasm, including fatal cases)
Use with caution in mild/moderate COPD only if benefits outweigh risks
🍬 Endocrine Considerations:
May mask signs of hypoglycaemia
(Caution in diabetes, especially labile or insulin-dependent)
May also mask signs of hyperthyroidism
👁️ Ocular Side Effects:
Can cause dry eyes
Caution in patients with corneal disease
💡 Tip to Reduce Systemic Absorption:
Nasolacrimal occlusion or closing eyelids for 1–2 minutes post-instillation
(Reduces systemic uptake)
