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Double-blind, placebo controlled study of acetyl-l-carnitine in patients with Alzheimer's dementia
Rai G, Wright G, Scott L, Beston B, Rest J, Exton-Smith AN.. Current medical research and opinion, 1990-01-01
Topic: Amyloid, tau and blood-test diagnosis
A randomized, double-blind, placebo-controlled, parallel-group clinical trial was carried out to compare 24-week periods of treatment with 1 g acetyl-l-carnitine twice daily and placebo in the treatment of patients with dementia of the Alzheimer type. A total of 36 patients entered the trial, of whom 20 patients (7 active, 13 placebo) completed the full 24 weeks. Whilst several of the efficacy indices showed little change in either group during the trial, there was an apparent trend for more improvement in the acetyl-l-carnitine group in relation to the Names Learning Test and a computerized Digit Recall Test, both related to aspects of short-term memory. Similarly, there was a trend for reaction time in the computerized classification test to show less deterioration in the active treatment group. Changes within groups, and changes between groups, failed to reach statistical significance, at least partially because of the small number of patients available for analysis. Two indices of overall therapeutic benefit showed a trend for less deterioration in the active-treatment group than in the placebo group. Nausea and/or vomiting occurred in 5 patients in the acetyl-l-carnitine group. Laboratory tests revealed no signs of drug toxicity. The results suggest that acetyl-l-carnitine may have a beneficial effect on some clinical features of Alzheimer-type dementia, particularly those related to short-term memory.
Key findings
- Two indices of overall therapeutic benefit showed a trend for less deterioration in the active-treatment group than in the placebo group.
- Laboratory tests revealed no signs of drug toxicity.
- The results suggest that acetyl-l-carnitine may have a beneficial effect on some clinical features of Alzheimer-type dementia, particularly those related to short-term memory.
Why it matters
In this 24-week trial of 36 patients, acetyl-l-carnitine showed trends toward less deterioration on some memory and reaction-time measures, but no changes reached statistical significance, partly because so few patients completed the study. The results are inconclusive and do not establish acetyl-l-carnitine as an effective treatment.
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Study details
- Participants36
- Evidence strengthHigh
How this study scored 53/100
Published in a peer-reviewed journal, and it is a randomised controlled trial. Scored zero for effect reported because the record does not state it.
| Component | Points | Why |
|---|---|---|
| Journal tier | 7 / 10 | Tier 3 — peer-reviewed journal (Current medical research and opinion) |
| Journal's citation record | 1 / 4 | Current Medical Research and Opinion: journal h-index 146 (OpenAlex, 2026-10-29) |
| Study design | 11 / 12 | A randomised controlled trial (from PubMed type “Randomized Controlled Trial”) |
| Strength of evidence | 5 / 5 | Rated “high” in our summary |
| Peer-review validation | 10 / 10 | Peer-reviewed. Published as an article in a named peer-reviewed journal. |
| How recent | 1 / 5 | 1990 — older than 20 years, still counted |
| Sample size | 1 / 4 | 36 participants |
| Effect reported | 0 / 3 | No effect size reported — scores zero (not stated in the record — scored 0) |
| Studied in people | 3 / 3 | Studied in people (participant count stated) |
| Randomised / blinded | 2 / 2 | Randomised and blinded or placebo-controlled (as stated in the record) |
| Times cited | 4 / 7 | Cited 84 times (OpenAlex, 2026-10-10) |
| Citations per year | 1 / 5 | 2.2 citations a year over 38 year(s) since 1990 |
| Impact for its field and year | 2 / 6 | Cited 1.8× the average for papers of its field and year (OpenAlex FWCI) |
| Cited by studies here | 1 / 6 | Cited by 2 other studies in this library |
| Still being cited | 0 / 4 | Cited 2 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | 2 / 4 | Last-listed author A. N. Exton‐Smith: h-index 33 (OpenAlex, whole career) |
| Institution's track record | 0 / 3 | Whittington Hospital: institution h-index 217 (OpenAlex) |
| Multi-centre collaboration | 0 / 3 | OpenAlex lists 1 institution(s) in 1 country — scores zero (affiliation lists can be incomplete) |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 2178869) |
| Free to read | 0 / 2 | Behind a paywall — scores zero |
| Total | 53 / 100 | — |
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Read the original
May need a subscription Unpaywall, Europe PMC and OpenAlex found no free copy of the full text (checked 10 Oct 2026), so the publisher may charge for it. The PubMed abstract is free.
Cite this study APA, Vancouver, BibTeX · download .bib or .ris
Built from the record alzhub holds for this paper, not looked up. Volume, issue and page numbers are not held in the record. Check the citation against the original before you use it.
APA 7th
Rai, G., Wright, G., Scott, L., Beston, B., Rest, J., & Exton-Smith, A. N. (1990). Double-blind, placebo controlled study of acetyl-l-carnitine in patients with Alzheimer's dementia. Current medical research and opinion. https://doi.org/10.1185/03007999009112690
Vancouver
Rai G, Wright G, Scott L, Beston B, Rest J, Exton-Smith AN. Double-blind, placebo controlled study of acetyl-l-carnitine in patients with Alzheimer's dementia. Current medical research and opinion. 1990. doi:10.1185/03007999009112690. PMID: 2178869.
BibTeX
@article{rai1990-2178869,
author = {Rai, G. and Wright, G. and Scott, L. and Beston, B. and Rest, J. and Exton-Smith, A. N.},
title = {{Double-blind, placebo controlled study of acetyl-l-carnitine in patients with Alzheimer's dementia}},
journal = {Current medical research and opinion},
year = {1990},
doi = {10.1185/03007999009112690},
pmid = {2178869},
url = {https://doi.org/10.1185/03007999009112690}
}
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