What is Telogen Effluvium?
Telogen effluvium is a form of diffuse, non-scarring hair shedding in which a larger than normal proportion of scalp follicles synchronously enter the telogen (resting) phase. This page summarises the research literature
Telogen effluvium is a form of diffuse, non-scarring hair loss in which an abnormally large proportion of scalp follicles shift synchronously into the telogen (resting) phase of the hair cycle, producing increased shedding roughly two to three months after the precipitating event. It is also referred to in the literature as telogen hair loss or telogen-phase shedding. It is classified as a non-inflammatory, non-scarring alopecia, and is distinguished from anagen effluvium, in which shedding follows direct insult to actively growing follicles. The evidence base assembled here does not supply a sequence, formula or molecular weight for telogen effluvium itself, as it is a clinical phenomenon rather than a single molecular entity.
The pharmacological work in this area centres on the glucagon-like peptide 1 receptor (GLP-1R) and the dual gastric inhibitory polypeptide (GIP)/GLP-1 receptor axis, because a safety signal concerning hair loss has emerged in patients receiving GLP-1 receptor agonists (GLP-1RAs) [2].
Research Studies
GLP-1 receptor agonists and hair loss in patients with type 2 diabetes mellitus
GLP-1RAs and dual GIP/GLP-1RAs are used to improve glycaemic control in patients with type 2 diabetes mellitus, and some of these drugs are also used to help with weight loss. In recent years, safety signals concerning a possible link between GLP-1RA therapies and hair loss have been emerging in the USA. The volume of prescriptions for these drugs in Europe is now increasing, and it can be expected that the number of cases of GLP-1RA-associated hair loss will therefore also increase in Europe over the coming years [2].
Pharmacological context and market expansion for GLP-1 receptor agonists
The commentary that forms the basis of this evidence considers the pharmacological context and market expansion for GLP-1RAs, and examines the emerging safety data on hair loss in the populations receiving them [2]. The observations are drawn from human clinical and pharmacovigilance material rather than from animal or in vitro models.
Dietary supplement intervention in GLP-1-associated telogen effluvium
A single-centre, open-label clinical study is evaluating whether a dietary supplement can reduce hair loss in women with GLP-1-associated telogen effluvium. Participants will use the supplement for 120 days. Researchers will evaluate hair loss, hair density, and hair growth through clinical assessments, hair measurements (trichogram), and participant questionnaires [1].
Trichogram and clinical assessment as outcome measures
In the registered study described above, the outcome measures are clinical assessment, trichogram hair measurements, and participant questionnaires, applied over a 120-day supplementation period in women with GLP-1-associated telogen effluvium [1]. These are the only outcome instruments specified in the evidence available here.
Comparison of the two evidence sources
| Item | Evidence [1] | Evidence [2] |
|---|---|---|
| Type | Registered clinical study | Commentary |
| Population | Women with GLP-1-associated telogen effluvium | Patients receiving GLP-1RAs and dual GIP/GLP-1RAs |
| Intervention or focus | Dietary supplement, 120 days | Pharmacological context and safety signal |
| Outcomes reported | Hair loss, hair density, hair growth; trichogram; questionnaires | Emerging safety signals; expected increase in European cases |
| Design | Single-centre, open-label | Commentary |
Geographic distribution of reported cases
Safety signals concerning a possible link between GLP-1RA therapies and hair loss have been emerging in the USA, while prescription volumes in Europe are now increasing, leading the authors to expect a corresponding rise in GLP-1RA-associated hair loss cases in Europe over the coming years [2].
Sex distribution of the studied population
The registered study of a dietary supplement in GLP-1-associated telogen effluvium is conducted in women [1]. The commentary on GLP-1RA-associated hair loss discusses patients on GLP-1RAs and dual GIP/GLP-1RAs more broadly, in the context of type 2 diabetes mellitus and weight loss [2].
Duration of observation in the supplement study
The supplement study specifies a 120-day period of use, with hair loss, hair density and hair growth evaluated across that window [1]. No efficacy result is reported in the evidence available here.
Limits of the current evidence
The evidence assembled here does not provide a sequence, formula or molecular weight for any compound, does not report animal-only or in vitro findings, and does not report completed efficacy outcomes for the supplement under study. The registered study is single-centre and open-label [1], and the second source is a commentary rather than a controlled trial [2].
If you are reading this for personal health reasons
The materials described on this page are supplied for laboratory research use only. We do not provide dosing information or medical guidance of any kind. Anyone considering a compound for themselves should speak to a licensed clinician.