General Guidance
- GP’s should refer ‘de novo’ cases to the primary or secondary neurology specialist teams before initiating pharmacological therapy if possible.
- Levodopa in combination with a dopa-decarboxylase inhibitor is the mainstay of treatment, however, after a ‘honeymoon’ of 5-10 years patients develop both predictable end-of-dose wearing off and unpredictable ‘on-off’ phenomena.
- Controlled-release formulations of levodopa have been developed in an attempt to reduce fluctuations. Unfortunately, their advantage over standard formulations is minimal and the main role of these more expensive preparations is in the control of symptoms overnight.
- Dopamine agonists are often used first line in patients with a life expectancy that exceeds the ‘honeymoon’ period. Approximately 60% of patients can be maintained on dopamine agonists for 2 or more years before levodopa must be added, however, no trials have been performed of sufficient length to confirm the benefits of this practice.
- Dopamine agonists are also used as ‘add- on’ to levodopa when the dose of the latter has risen to about 600mg.
- All the agonists have been shown to reduce fluctuations, increase ‘on’ time and limit the severity of the ‘off’ state. Side effects are common, particularly in older patients (nausea, hallucinations, postural hypotension) and treatment is expensive.
- All newer agonists have been shown to be slightly better than bromocriptine. Few direct comparisons have been performed. In practice, it is often worth changing from one agonist to another if side effects are a problem, since there is variability in a given patient’s tolerance to the different drugs.
- Selegiline is given once daily and has been shown to be of modest benefit. Previously thought to have ‘neuroprotective’ effects, but this has now been largely discounted.
- Entacapone (COMT inhibitor) is licensed to be given with each dose of levodopa in order to increase ‘on’ time in fluctuating patients, although dyskinesias can be increased. It remains unclear whether COMT inhibition should be used early or late in the disease and before or after dopamine agonists.
Recommended drugs
All to be initiated by the specialist team and then continued prescribing by the GP
Co-Beneldopa ££
Co-Careldopa £££
Amantadine (evaluate after 6 months) £££
Trihexyphenidyl £££
Rotigotine patch (for patients unable to tolerate oral agents) £££££
Levodopa/Carbidopa/Entacapone - prescribe as Stanek
Dopamine agonists
Ropinirole £££ - when prescribing as modified release preferred brand to be prescribed is Ipinnia XL Prolonged-Release Tablets
Pramipexole £££ - when prescribing as modified release preferred brand to be prescribed is Pipexus prolonged-release tablets, not generic prescribing
Apomorphine £££
COMT inhibitor
Entacapone £££
Opicapone £££
Monoamine-oxidase-B inhibitors
1st Line - Selegiline ££
2nd Line - Selegeline oral lyophilisate (Zelapar) £££
3rd Line - Rasagiline ££££
Safinamide £££
Drug Traffic Light Key:
Green – On Formulary
Amber – Restricted use, see local guidelines
Purple – Specialist use/initiation
Red – Non Formulary
Relative Costs Key (where indicated):
£££££ - high
£££ - moderate
£ - low