Parkinson’s Disease – Symptoms, Diagnosis, and Treatment Options

 

*Introduction*

*Parkinson’s Disease (PD)* is a *progressive neurodegenerative disorder* that primarily affects movement. It occurs due to the loss of *dopamine-producing neurons* in the brain. It mostly affects individuals over 60 years old but can occur earlier. The hallmark features include *tremors*, *rigidity*, *bradykinesia*, and *postural instability*.

*Pathophysiology*

Parkinson’s disease results from the *degeneration of dopaminergic neurons* in the *substantia nigra pars compacta*, a part of the *basal ganglia*. This leads to a *dopamine deficiency*, impairing communication between the basal ganglia and motor cortex.

*Key points:*

- ↓ Dopamine → ↓ stimulation of motor pathways  

- Formation of *Lewy bodies* (abnormal α-synuclein protein aggregates)  

- Progressive loss of motor control and cognitive decline in later stages

*Symptoms and Signs*

*Motor Symptoms:*

- *Resting tremor* (pill-rolling tremor)

- *Bradykinesia* (slowness of movement)

- *Muscle rigidity*

- *Postural instability*

- Shuffling gait

- Masked facial expression

*Non-Motor Symptoms:*

- Depression, anxiety

- Cognitive decline (Parkinson’s dementia)

- Constipation

- Sleep disturbances

- Loss of smell (anosmia)

- Urinary problems

*Diagnosis*

Parkinson’s is diagnosed *clinically*, based on history and symptoms. No definitive blood test exists.

*Diagnostic tools:*

- *Neurological exam*

- *Response to Levodopa* (diagnostic trial)

- *MRI/CT* to rule out other causes

- *DaTscan (SPECT)* may be used in uncertain cases

*Treatment*

There’s *no cure*, but several medications and therapies help manage symptoms.

*Drugs for Parkinson’s Disease*

1. *Levodopa + Carbidopa*

- *Use:* Most effective for motor symptoms

- *Mechanism:* Levodopa converts to dopamine; Carbidopa prevents peripheral conversion

- *Dosage:* Start with 100/25 mg TID, titrate up

- *Side Effects:* Nausea, dyskinesia, hallucinations, "on-off" effect

2. *Dopamine Agonists* (e.g., Pramipexole, Ropinirole)

- *Use:* Early stages or adjunct to Levodopa

- *Side Effects:* Sleep attacks, impulse control disorders, hallucinations

3. *MAO-B Inhibitors* (e.g., Selegiline, Rasagiline)

- *Use:* Mild symptoms; delays Levodopa need

- *Side Effects:* Insomnia, headache, nausea

4. *COMT Inhibitors* (e.g., Entacapone, Tolcapone)

- *Use:* Extend Levodopa effect

- *Side Effects:* Diarrhea, liver toxicity (Tolcapone)

5. *Anticholinergics* (e.g., Benztropine, Trihexyphenidyl)

- *Use:* Tremor in younger patients

- *Side Effects:* Dry mouth, confusion, urinary retention

6. *Amantadine*

- *Use:* Mild symptoms or dyskinesia control

- *Side Effects:* Livedo reticularis, ankle edema, confusion

*Non-Drug Therapies*

- *Physiotherapy:* Improve mobility and balance  

- *Speech therapy:* Help with speech and swallowing  

- *Deep Brain Stimulation (DBS):* For advanced, drug-resistant cases  

*Conclusion*

Parkinson’s Disease is a chronic, progressive condition requiring lifelong management. *Early diagnosis* and *individualized treatment* significantly improve quality of life. Combining *medications*, *lifestyle changes*, and *supportive therapies* can help manage the disease effectively.