This grade answers one narrow question: how strong is the public evidence and safety record behind this drug, and how clean is its money trail and court record? It is not a verdict on whether the drug is right for you.
Listed on the WHO Model List of Essential Medicines: a global expert panel judged it among the medicines a health system should always have, on evidence of value, not marketing.
INDICATIONS AND USAGE Sedative Anticonvulsant- For the treatment of generalized and partial seizures.
CONTRAINDICATIONS Phenobarbital is contraindicated in patients who are hypersensitive to barbiturates, in patients with a history of manifest or latent porphyria, and in patients with marked impairment of liver function or respiratory disease in which dyspnea or obstruction is evident.
WARNINGS 1. Habit-Forming Phenobarbital may be habit-forming. Tolerance and psychological and physical dependence may occur with continued use ( see Drug Abuse and Dependence and Pharmacokinetics under Clinical Pharmacology ). Patients who have psychologic dependence on barbiturates may increase the dosage or decrease the dosage interval without consulting a physician and may subsequently develop a physical dependence on barbiturates. In order to minimize the possibility of overdosage or the development of dependence, the prescribing and dispensing of sedative-hypnotic barbiturates should be limited to the amount required for the interval until the next appointment. Abrupt cessation after prolonged use in a person who is dependent on the drug may result in withdrawal symptoms, including delirium, convulsions, and possibly death. Barbiturates should be withdrawn gradually from any patient known to be taking excessive doses over long periods of time ( see Drug Abuse and Dependence ). 2. Acute or Chronic Pain Caution should be exercised when barbiturates are administered to patients with acute or chronic pain, because paradoxical excitement could be induced or important symptoms could...
ADVERSE REACTIONS The following adverse reactions have been reported: CNS Depression- Residual sedation or "hangover," drowsiness, lethargy, and vertigo. Emotional disturbances and phobias may be accentuated. In some persons, barbiturates such as phenobarbital repeatedly produce excitement rather than depression, and the patient may appear to be inebriated. Irritability and hyperactivity can occur in children. Like other nonanalgesic hypnotic drugs, barbiturates such as phenobarbital, when given in the presence of pain, may cause restlessness, excitement, and even delirium. Rarely, the use of barbiturates results in localized or diffuse myalgic, neuralgic, or arthritic pain, especially in psychoneurotic patients with insomnia. The pain may appear in paroxysms, is most intense in the early morning hours, and is most frequently located in the region of the neck, shoulder girdle, and upper limbs. Symptoms may last for days after the drug is discontinued. Respiratory/Circulatory- Respiratory depression, apnea, circulatory collapse. Allergic- Acquired hypersensitivity to barbiturates consists chiefly in allergic reactions that occur especially in persons who tend to have asthma, urticar...
Source: FDA SPL label for Phenobarbital (Pharmaceutical Associates, Inc.), effective 20220105. Full label on DailyMed.
These are counts of reports people filed, not rates of harm. Anyone can file one, and nobody checks whether the drug was the cause. Millions of doses are taken for every report sent, so the useful part is how this drug compares with the average across all drugs.
| 2019 | 2020 | 2021 | 2022 | 2023 | 2024 | 2025 | 2026 |
|---|---|---|---|---|---|---|---|
| 1,344 | 1,283 | 1,337 | 1,172 | 1,311 | 1,171 | 1,004 | 406 |
6,352 reports blaming this drug for every million Medicare prescriptions filled, which is 2.3× the typical drug on this site. (2,535 reports in 2024–2026, against 399,060 Medicare fills in one year. This is the one number here that accounts for how many people take the drug.)
Source: the FDA's Adverse Event Reporting System (FAERS). Reports are voluntary and unverified. Drugs that are prescribed a lot, in the news, or in lawsuits attract more reports, so the percentages are compared with the whole database to correct for that partly, not fully.
| Date | Class | Firm | Reason |
|---|---|---|---|
| 03/2022 | Class II | Vitae Enim Vitae Scientific, Inc. | Lack of Assurance of Sterility: deviations from Current Good Manufacturing Practices (CGMP) that call into question the sterility of products intended to be sterile. |
| 03/2022 | Class II | Vitae Enim Vitae Scientific, Inc. | Lack of Assurance of Sterility: deviations from Current Good Manufacturing Practices (CGMP) that call into question the sterility of products intended to be sterile. |
| 10/2016 | Class II | West-Ward Pharmaceuticals Corp. | Failed Dissolution Specifications: Phenobarbital Tablets have an out of specification for dissolution at the 12 month stability time point |
Class I = reasonable probability of serious harm. Class II = temporary or reversible harm. Class III = unlikely to harm. Most generic recalls are manufacturing or labeling defects for one lot, not a verdict on the molecule.
Counts measure how much evidence exists and how transparent it is, not how big the benefit is. For that, ask your prescriber: if 100 people like me took this, how many would get better because of it, and how many would be harmed? (Doctors call these the "number needed to treat" and "number needed to harm.") It differs by condition and is the number drug ads leave out. Sources: PubMed, ClinicalTrials.gov.
In 2024, drug companies reported $0 in payments to US physicians and hospitals tied to this drug across 0 transactions.
No pending federal MDL names this drug or its brands.
Not named in any federal pharmaceutical settlement of $100M or more on record.
Sources: CMS Open Payments (Sunshine Act); Judicial Panel on Multidistrict Litigation pending docket list; DOJ settlements as tabulated on Wikipedia with links to the primary record. State-court and individual suits are not included.
| Product | Fills | $/fill |
|---|---|---|
| Phenobarbital | 398,979 | $29 |
| Phenobarbital Sodium | 81 | $1,173 |
1 drug in the same class grades a letter or more higher than phenobarbital on this site. Worth asking whether one of them would do the same job for you.
Same ATC pharmacological class, graded ones first, best grade at the top. Being in the same class does not make them interchangeable for your condition; it makes them worth asking about.