Could you help unlock a new treatment for hallucinations?
We’re looking for volunteers to join our UK-wide research trial, called TOP HAT.
By taking part, you'll help us prove if a safe, existing medication called ondansetron can improve quality of life for thousands of families.
We're looking for people with Parkinson’s or Lewy body dementia who:
• experience visual hallucinations, seeing things that aren't there, at least once a week
• are on a stable dose of Parkinson’s or Lewy body dementia medication
• You’ll have expert care and in-person health checks (including a blood sample and heart rhythm check) to make sure you're safe and supported.
• Over 12 weeks, we’ll post you either ondansetron or dummy tablets to take alongside your usual medication. The team will stay in close contact via phone, video and 3 visits to a local hospital.
How you can take part
This trial is being managed by Dr Olga Zubko. The first step is to contact Olga, who will give you more information about TOP HAT and whether it's right for you.
Get in touch with the TOP HAT team: If you'd prefer to speak on the phone, you can call the team on 020 3108 9073. Don't worry if we aren't at our desks, just leave a voicemail with your details, and we’ll call you back for a friendly chat.
Check your location: See our list of research sites. We have locations across the UK, from Belfast to Plymouth.
Speak to your specialist: If you’re noticing new or worsening hallucinations, contact your specialist or Parkinson’s nurse as soon as you can.
Find out more about how the trial works in our frequently asked questions document.
Making a difference: Maria and Desmond on the TOP HAT trial
“I’d really encourage anyone thinking about it to take part. It was so easy, just one more pill. And the research visits are just the same as the routine appointments. It was like having extra consultations, we felt like VIPs!”
More opportunities to get involved in research
Join our Research Support Network to receive emails with opportunities to take part and have a say in research in your local area.
We're bringing together people driven to help find a cure and better treatments for Parkinson's.
Parkinson's UK
Neuroprogressive and Dementia Network, Old Pharmacy Building, Western General Hospital, Crewe Road South
Edinburgh
EH4 2UX
United Kingdom
Queen Elizabeth University Hospital
Clinical Trials Unit
1345 Govan Road
Glasgow
G51 4TF
United Kingdom
Clinical Trials Office, Ward 25, University Hospital Monklands, Monkscourt Avenue,
Airdrie
ML6 0JS
United Kingdom
Research Department, 4th floor Academic Centre, University Hospital of Llandough
Penarth
CF64 2XX
United Kingdom
Belfast Health and Social Care Trust, Room 9, 4th Floor, Dunluce Heath Centre, 1 Dunluce Ave
Belfast
BT9 7HR
United Kingdom
Salford Royal NHS Foundation Trust
Stott Lane
Salford
M6 8HD
United Kingdom
Leeds and York Partnership NHS Foundation Trust
Research and Development, 1st Floor North Wing, St Mary’s House, St Mary’s Road
Leeds
LS7 3JX
United Kingdom
Pennine Acute Hospitals NHS Trust, Ward 19 Clinical Research Unit, Fairfield General Hospital
Bury
BL9 7TD
United Kingdom
North Tyneside Hosptial
Rake Lane
North Shields
NE29 8NH
United Kingdom
Sherwood Forest Hospitals NHS Foundation Trust
Kings Mill Hospital
Sutton In Ashfield
NG17 4JL
United Kingdom
The Shrewsbury and Telford Hospital NHS Trust, Research & Innovation Department, The Royal Shrewsbury Hospital, Mytton Oak Road,
Shrewsbury
SY3 8XQ
United Kingdom
Coventry and Warwickshire Partnership NHS Trust, Wayside Business Park, Wayside House, Wilsons Lane,
Coventry
CV6 6NY
United Kingdom
Redditch and Bromsgrove Older Adult CMHT New Haven, Princess of Wales Community Hospital, Stourbridge Road
Bromsgrove
B61 0BB
United Kingdom
Luton and Dunstable NHS Foundation Trust
Ground Floor Nova House
Lewsey Road
Luton
LU4 0DZ
United Kingdom
Larch House 2nd Floor, Research & Development, West Suffolk NHS Foundation Trust, Hardwick Lane,
Bury St Edmunds
IP332QZ
United Kingdom
Neurology Department Atkinson Morley Wing Ground Floor St George’s University Hospital
Blackshaw Road
London
SW17 0QT
United Kingdom
University College London Hospital
Leonard Wolfson Experimental Neurology Centre CRF National Hospital for Neurology and Neurosurgery
Queen Square
London
WC1N 3BG
United Kingdom
Research Delivery Unit, Lakeside, West Middlesex Hospital, Twickenham Rd
Isleworth
TW7 6AF
United Kingdom
South West London and St George’s Livingston House
2-6 Queens Road,
Teddington, London
TW11 0LB
United Kingdom
Research & Development, Two Bridges, Guildford Street,
Chertsey
KT16 9AU
United Kingdom
Research and Development Office, Chertsey House, St Peter's Hospital, Guilford Lane,
Chertsey
KT16 0PZ
United Kingdom
Royal Berkshire Hospital
London Road
Reading
RG1 5AN
United Kingdom
Southend University Hospital Prittlewell Chase
Westcliff-on-Sea Essex
SS0 0RY
United Kingdom
Queen's Hospital
Barking, Havering and Redbridge University Hospitals NHS Trust
Neuro Research office, Neurophysiology Department, Orange Zone, Ground Floor
Romford
RM7 0AG
United Kingdom
The Lind Research Centre, Level 5, Terence Lewis Building, University Hospitals Plymouth NHS Trust
Plymouth
PL6 8DH
United Kingdom
Southern Heath Memory Assessment and Research Centre (MARC), Tom Rudd Unit, Moorgreen Hospital, Botley Road, West End,
Southampton
SO30 3JB
United Kingdom
Christchurch Hosptial
Fairmile Road
Christchurch
BH23 2JX
United Kingdom