Makindo Medical Notes

🧠 About Parkinson’s Drug Management

• Parkinson’s disease is due to dopamine deficiency in the basal ganglia.
• Main goal: restore dopaminergic activity, reduce motor symptoms, and improve quality of life.
• Treatment is individualised based on age, frailty, cognition, and comorbidities.

💊 Main Drug Classes & Dosing

• 1️⃣ Levodopa + DDC inhibitor (co-careldopa, co-beneldopa)
  • First-line in patients >70 or with cognitive impairment.
  • Dose:
    • Start low (e.g. co-careldopa 12.5/50 mg TDS) and titrate.
    • Usual range: 50/200 mg TDS–QDS. Adjust according to response.
  • ⚠️ Side effects: dyskinesias, motor fluctuations (on–off), hallucinations, hypotension.
• 2️⃣ Dopamine Agonists (pramipexole, ropinirole, rotigotine patch, apomorphine)
  • Pramipexole: start 0.125 mg TDS → titrate to max 1.5 mg TDS.
  • Ropinirole: start 0.25 mg TDS → titrate; XL forms available.
  • Rotigotine patch: start 2 mg/24 h → titrate to max 16 mg/24 h.
  • Apomorphine (SC): rescue injections or continuous infusion under specialist supervision.
  • ⚠️ Side effects: impulse control disorders, hallucinations, oedema, somnolence.
• 3️⃣ MAO-B Inhibitors (selegiline, rasagiline, safinamide)
  • Selegiline: 5 mg OD or BD.
  • Rasagiline: 1 mg OD.
  • Safinamide: 50 mg OD → may increase to 100 mg OD.
  • ⚠️ Side effects: insomnia, hallucinations, hypertensive crisis with tyramine foods (rare).
• 4️⃣ COMT Inhibitors (entacapone, opicapone, tolcapone)
  • Entacapone: 200 mg with each levodopa dose (max 10/day).
  • Opicapone: 50 mg OD at bedtime.
  • Tolcapone: 100–200 mg TDS (⚠️ hepatotoxicity risk).
  • ⚠️ Side effects: diarrhoea, urine discolouration, hepatotoxicity (tolcapone).
• 5️⃣ Amantadine
  • Dose: 100 mg OD–BD (max 300 mg/day).
  • Useful for levodopa-induced dyskinesias.
  • ⚠️ Side effects: livedo reticularis, ankle oedema, confusion.
• 6️⃣ Anticholinergics (trihexyphenidyl, procyclidine)
  • Dose: Trihexyphenidyl 1 mg OD–BD (max 15 mg/day).
  • More effective for tremor-predominant PD in young patients.
  • ⚠️ Side effects: confusion, urinary retention, dry mouth → avoid in elderly.

📋 NICE Simplified Pathway

• 👴 Older (>70) or cognitive impairment → Levodopa.
• 🧑 Younger (<70), no cognitive issues → Dopamine agonist or MAO-B inhibitor.
• ⚡ Escalate stepwise with COMT inhibitors, dopamine agonists, or amantadine if fluctuations develop.
• Specialist referral at all treatment stages.

🚑 Management When Unable to Swallow (NBM)

• 💧 Dispersible levodopa (Madopar® dispersible): can be given via NG tube.
• 🩹 Rotigotine patch: provides continuous dopaminergic stimulation.
• 💉 Apomorphine (SC injection/infusion): specialist initiation, useful for acute rescue.
• 📡 Duodopa® (levodopa–carbidopa intestinal gel): continuous PEG-J infusion.
• ⚠️ Never stop dopaminergic drugs suddenly → risk of Parkinsonism–Hyperpyrexia Syndrome.

⚠️ Key Cautions & Monitoring

• Impulse control disorders (gambling, hypersexuality, binge eating) with dopamine agonists.
• Hallucinations & psychosis with dopaminergic drugs.
• Postural hypotension with levodopa and dopamine agonists.
• Monitor LFTs with tolcapone.
• Adjust doses in renal impairment for amantadine.

Surgical

• 🧩 Deep Brain Stimulation (DBS): For advanced disease, subthalamic nucleus/globus pallidus targets.

Multidisciplinary Care

• 👩‍⚕️ Nurse specialist: medication timing, education.
• 🏃 Physiotherapy: balance, gait training.
• 🗣️ SLT: dysarthria, dysphagia.
• 🛠️ OT: adaptive aids, safety at home.

Hospital/Acute Considerations

• ⏰ Never delay PD meds (risk of severe deterioration, even NBM use NG or rotigotine patch).
• 🚫 Avoid antidopaminergic drugs (metoclopramide, haloperidol, prochlorperazine).

Non-Motor Complications

• 🚽 Constipation → macrogol, fluids, mobility.
• 📉 Orthostatic hypotension → fludrocortisone, midodrine.
• 🦠 Recurrent UTIs → hydration, constipation prevention.
• 👻 Psychosis/hallucinations → quetiapine, clozapine.
• 🧩 Dementia → rivastigmine (watch for tremor worsening).

Advance Care Planning

• 📝 Advance directives, lasting power of attorney.
• 🤝 Signposting to community support and respite care.

References

• Visanji et al. Acta Neuropathologica Comms 2013

Cases — Parkinson’s Disease with Complications

• Case 1 — Motor Fluctuations (“Wearing Off”) ⏳: A 68-year-old man on levodopa for 7 years reports that tremor and rigidity return 3 hours after each dose. He experiences “on–off” fluctuations through the day. Complication: Motor fluctuations due to long-term levodopa use. Management: Shorten levodopa dosing intervals; add COMT inhibitor (entacapone) or dopamine agonist.
• Case 2 — Dyskinesias 💃: A 62-year-old woman develops involuntary writhing movements of her trunk and arms about 30 minutes after each levodopa dose. Complication: Levodopa-induced dyskinesia. Management: Lower levodopa dose; add amantadine; consider deep brain stimulation if severe.
• Case 3 — Parkinson’s Disease Dementia 🧠: A 75-year-old man with 10 years of PD develops progressive memory loss, visual hallucinations, and difficulty with daily tasks. Complication: Parkinson’s disease dementia. Management: Rivastigmine (first-line cholinesterase inhibitor); review dopaminergic drugs that worsen hallucinations.
• Case 4 — Autonomic Dysfunction 💧: A 70-year-old woman with PD reports frequent faints on standing, constipation, and urinary urgency. BP falls from 135/80 supine to 95/60 standing. Complication: Autonomic dysfunction (orthostatic hypotension, bladder involvement). Management: Non-pharmacological (slow position changes, compression stockings, ↑ salt/fluid); consider fludrocortisone or midodrine.
• Case 5 — Impulse Control Disorder 🎰: A 60-year-old man on pramipexole for PD develops compulsive gambling and hypersexuality, which his wife finds distressing. Complication: Dopamine agonist–induced impulse control disorder. Management: Reduce/stop dopamine agonist; switch to levodopa-based regimen; behavioural support.

Teaching Commentary 🧠

Parkinson’s disease complications can be divided into: - Motor: fluctuations (“wearing off”), dyskinesias. - Neuropsychiatric: dementia, hallucinations, depression, impulse control disorders. - Autonomic: postural hypotension, constipation, bladder dysfunction, erectile dysfunction. - Sleep: REM sleep behaviour disorder, insomnia. Complications often reflect both disease progression and treatment side effects. Management requires balancing dopaminergic therapy, adding adjuncts (COMT/MAO-B inhibitors), and addressing non-motor symptoms with MDT support. Deep brain stimulation is an option in selected patients with refractory motor fluctuations.