Evaluation of the effectiveness of Omega-3 supplementation and Olfactory rehabilitation in patients with olfactory dysfunction

Evaluation of the effectiveness of Omega-3 supplementation and olfactory training in patients with olfactory dysfunction

Status

Active, not recruiting

Phases

Phase 1

Study type

Interventional

Source

IRCT

Registry ID

IRCT20210414050971N2

Enrollment

Registered

2026-01-28

Start date

2026-02-18

Completion date

Unknown

Last updated

2026-02-02

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

This study investigates Olfactory Dysfunction (OD), which is defined as reduced or complete loss of smell (hyposmia or anosmia). This condition happens due to a variety of causes including viral infections (e.g. post COVID-19 pandemic), head trauma, sinusitis and skull base surgeries. OD has severe impact on quality of life, posing safety risks (inability to smell gas leaks, smoke, or spoiled food) and causing psychological distress (depression, anxiety, social isolation) and nutritional issues.

Interventions

Intervention 1: Control group: 20 people are the control group with no treatment. Intervention 2: Intervention group: 20 people are the olfactory training group and receive olfactory training over 16

Eligibility

Sex/Gender

All

Age

18 Years to 60 Years

Inclusion criteria

Inclusion criteria: Olfactory dysfunction Confirmed olfactory dysfunction by the Sniffin’s Sticks test

Exclusion criteria

Exclusion criteria: Severe nasal septum deviation Psychiatric disorders Pregnancy Sinusitis, Nasal or brain tumors Alcohol consumption Nasal polyps Occupational exposure to unfavorable conditions (e.g., working in paint factories or with heavy metals) Congenital anosmia

Design outcomes

Primary

Measure	Time frame
Change in olfactory function scores (Threshold, Discrimination, and Identification; TDI score) measured by the Sniffin’s Sticks test from baseline to 16 weeks after intervention. Timepoint: Baseline (T0): Measurement is taken before the start of the intervention. Endpoint (T1): Measurement is taken once, immediately after the completion of the 16-week intervention period. Method of measurement: Before and after the intervention, the Sniffin’ Sticks olfactory test is performed. The Sniffin’ Sticks test lasts 30–45 minutes and includes 16 pens or sticks, in which the pads contain the target scent instead of ink. The olfactory substance is presented at a concentration above the detection threshold. The extract is held 2 cm from the nostrils, and the patient sniffs for 2–3 seconds. The total TDI score is calculated by summing the olfactory threshold (T), discrimination (D), and identification (I) scores.	—

Measure

Time frame

Change in olfactory function scores (Threshold, Discrimination, and Identification; TDI score) measured by the Sniffin’s Sticks test from baseline to 16 weeks after intervention. Timepoint: Baseline (T0): Measurement is taken before the start of the intervention. Endpoint (T1): Measurement is taken once, immediately after the completion of the 16-week intervention period. Method of measurement: Before and after the intervention, the Sniffin’ Sticks olfactory test is performed. The Sniffin’ Sticks test lasts 30–45 minutes and includes 16 pens or sticks, in which the pads contain the target scent instead of ink. The olfactory substance is presented at a concentration above the detection threshold. The extract is held 2 cm from the nostrils, and the patient sniffs for 2–3 seconds. The total TDI score is calculated by summing the olfactory threshold (T), discrimination (D), and identification (I) scores.

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Countries

Iran (Islamic Republic of)

Contacts

Public ContactRafieh Alizadeh

Iran University of Medical Sciences

alizadeh.r@iums.ac.ir+98 912 091 5313

Outcome results

None listed

Source: IRCT (via WHO ICTRP) · Data processed: Feb 7, 2026