NAC for Head Trauma-induced Anosmia

Study Overview
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Brief Summary
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This study will compare administration of N-Acetyl Cysteine (NAC) versus placebo for the treatment of olfactory loss due to head injury. The hypothesis is that treatment with NAC acutely after head injury will result in improved olfactory function

Official Title
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Early N-Acetyl Cysteine Treatment for Head Trauma-induced Anosmia

Conditions
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Anosmia, Head Trauma

Intervention / Treatment
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* Drug: N Acetyl Cysteine
* Drug: Placebo oral capsule


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Admitted to Ryder Trauma Center for observation acutely following head injury (i.e. concussion), with documented hyposmia or anosmia by University of Pennsylvania Smell Identification Test (SIT). Male or female, aged 18 years or older Provision of signed and dated informed consent form Stated willingness to comply with all study procedures and availability for the duration of the study Ability to take oral medication and be willing to adhere to the NAC regimen For females of reproductive potential: use of highly effective contraception for at least 1 month prior to screening and agreement to use such a method during study participation and for an additional 4 weeks after the end of NAC administration Exclusion Criteria: Severe trauma requiring ongoing inpatient treatment beyond 48 hours Pregnancy (based on urine screening) or lactation Known allergic reactions to components of NAC, such as Mucomyst Currently taking nitrates such as nitroglycerine and/or isosorbide regularly Currently taking azathioprine (Imuran) or cyclophosphamide (Cytoxan) Known diagnosis of cystinuria (renal condition in which cysteine supplement should be avoided) Febrile illness within 1 week Treatment with another investigational drug or other intervention within 3 months Active sinonasal disease by imaging and/or nasal exam, i.e. rhinosinusitis, nasal polyps Adults unable to consent Prisoners, employees or subordinates Individuals who are not yet adults (infants, children, teenagers). This population is excluded because efficacy has not yet been established in adults.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: NAC Group<br>NAC group will be administered orally as a 4 gram loading dose, followed by 2 g PO BID for 4 days, then 1.5 g PO BID for 2 days | Drug: N Acetyl Cysteine<br>* 2 g PO BID for 4 days, then 1.5 g PO BID for 2 days<br>|
| Placebo Comparator: Placebo Group<br>Placebo group will be administered orally as a 4 gram loading dose, followed by 2 g PO BID for 4 days, then 1.5 g PO BID for 2 days | Drug: Placebo oral capsule<br>* 2 g PO BID for 4 days, then 1.5 g PO BID for 2 days<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Olfactory Function | Olfactory function will be measured using the University of Pennsylvania Smell Identification Test (UPSIT). The UPSIT is a self-administered 40-item test involving microencapsulated (scratch-and-sniff) odors with a forced-choice design. The total score ranges from 0-40 with the higher score indicating better olfactory function. | 4 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Quality of Life Questionnaire | Quality of life will be measured using the questionnaire for Olfactory Disorders (QOD). QOD has a total score from 0-75 with the higher score indicating a better quality of life. | 4 months |