Class II · Moderate risk
Unisom
CGMP Deviations; detection of Nitrosamine Drug Substance-Related Impurities (NDSRI), N-nitroso-desmethyl-diphenhydramine (n-dph), above the FDA Recommended Intake Limit
Unisom
Class II — Moderate risk. May cause temporary or reversible harm; serious harm unlikely.
Why it was recalled
CGMP Deviations: Nitrosamine Drug Substance Related Issue impurity above the daily acceptable intake limit defined by the Food and Drug Administration.
Cause type: Nitrosamine impurity
Trace nitrosamine impurities such as NDMA, NDEA or NMBA found above the acceptable daily limit. Nitrosamines are probable human carcinogens that can form during manufacturing or storage. This is the cause behind the large valsartan, losartan and ranitidine (Zantac) recalls. All nitrosamine impurity recalls.
What was recalled
Unisom, SleepMelts, Diphenhydramine HCl tablets, 25 mg, Nighttime Sleep-Aid, 4 x 8 blister packs per carton, Cherry flavor, Manufactured by Adare Pharmaceuticals, Inc., Dist. by Chattem, Inc., P.O. Box 2219, Chattanooga, TN 37409, UPC # 0 41167 0014 0
Drug: Diphenhydramine Category: Allergy & Cold Medication
- Recalling firm
- Chattem Inc
- Origin
- TN, United States
- Initiated by
- Voluntary: Firm initiated
- FDA recall number
- D-0266-2025 · FDA notice
Check, then ask. Class II means harm is possible but usually temporary or reversible. Find the lot number on your package; if it matches, ask your pharmacist about a replacement. Do not simply stop a prescribed medication on your own - the gap can be riskier than the recall.
Other Diphenhydramine recalls
See all
Class III · Low risk
Diphenhydramine HCl 50 mg
Labeling: Not Elsewhere Classified: Tablets/Capsules imprinted with wrong ID.
Class III · Low risk
Diphenhydramine HCl 25 mg
Labeling: Not Elsewhere Classified: Tablets/Capsules imprinted with wrong ID.
Class III · Low risk
Diphenhydramine HCl 25 mg
Labeling: Not Elsewhere Classified: Tablets/Capsules imprinted with wrong ID.
Class I · High risk
Robitussin Honey CF Max Nighttime Adult
Microbial Contamination of Non-Sterile Products
Other recalls by Chattem Inc
All 2025 recalls
Class II · Moderate risk
Unisom
CGMP Deviations; detection of Nitrosamine Drug Substance-Related Impurities (NDSRI), N-nitroso-desmethyl-diphenhydramine (n-dph), above the FDA Recommended Intake Limit
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