The short version
- A crew member may bring a Schedule II to V prescription into or out of the US for personal use only if it stays in the original dispensed container and is declared to a customs officer[1].
- A US resident may import no more than 50 dosage units of controlled medication bought abroad. The cap does not apply to medication prescribed by a DEA registrant in the US[1].
- Unmanifested opiates found aboard expose the master and owner to a penalty of $1,000 per ounce, and clearance can be withheld until it is paid[3].
- On inspected vessels a crew member may take a prescription drug only if it does not cause intoxication[4]. A valid prescription can turn a positive drug test negative, but the burden of proof sits with the mariner[7].
Crew medication and the ship’s chest are two different legal stocks
Most vessel medication problems start when the two are mixed. The chest belongs to the vessel. Its controlled substances are held under the general supervision of a DEA-registered medical officer, or bought by the master through a written requisition, under 21 CFR 1301.25[9].
A crew member’s own prescription belongs to the crew member. It enters the country under a separate rule, 21 CFR 1301.26, written for any individual carrying medication for personal use[1]. The officer cannot top up a mariner’s supply from the chest as routine: chest stock may be distributed only to persons under the medical officer’s supervision, except under the disposal rules in part 1317[9].
| Question | Ship’s medicine chest | Crew member’s own prescription |
|---|---|---|
| Legal basis | 21 CFR 1301.25[9] | 21 CFR 1301.26[1] |
| Who controls it | Medical officer or master | The individual it was dispensed to |
| Customs paperwork | Ship’s Stores Declaration, CBP Form 1303[2] | Personal declaration; Crew Member’s Declaration, CBP Form 5129, if articles will be landed[1][2] |
| Container | Chest stock with records | Original container it was dispensed in[1] |
| Reports | Medical officer and master reports under 1301.25[9] | Prescription details on the label or from the pharmacy[1] |
For the chest side in full, read 21 CFR 1301.25 explained. For who may write a prescription at sea, see who can prescribe medication on a ship.
What 21 CFR 1301.26 requires when a mariner enters or leaves the US
The exemption covers controlled substances in schedules II, III, IV and V that the individual obtained lawfully for personal medical use[1]. Schedule I is not in the list. Two conditions apply to everyone.
- Original container. The medication stays in the container it was dispensed in[1]. A weekly pill organiser is not that container.
- Declaration to customs. The individual declares that the substance is for personal use and gives the trade or chemical name and the schedule symbol from the label. If the label does not show the name, the declaration gives the pharmacy or practitioner’s name and address and the prescription number[1].
A third condition applies to US residents only: no more than 50 dosage units, combined, of controlled medication obtained abroad. The rule defines a resident by actual principal dwelling place, and the cap does not apply to medication prescribed in the US by a DEA registrant[1].
Worked example
A US-resident engineer fills a 30-day tramadol prescription in Singapore mid-contract. At twice daily that is 60 tablets. The 50-unit cap applies because it was obtained abroad[1]. The fix is to fill before departure: a US prescription from a DEA registrant carries no 50-unit cap[1].
Why the master should know what the crew is carrying
The inward manifest includes a Crew’s Effects Declaration, CBP Form 1304. Articles that should have been manifested and were not are subject to forfeiture, and the master faces a penalty equal to their value[2].
Narcotics raise the stakes. Under 19 U.S.C. 1584(a)(2), unmanifested heroin, morphine, cocaine, isonipecaine or opiate found aboard makes the master, owner or anyone responsible liable to $1,000 per ounce; for marihuana it is $500 per ounce[3]. The penalty is a lien on the vessel and clearance may be withheld until it is paid or bonded[3].
| Found unmanifested aboard[3] | Penalty per ounce | Defence available |
|---|---|---|
| Heroin, morphine, cocaine, isonipecaine or opiate | $1,000 | Common carrier only, if no officer or owner knew or could have known with the highest degree of care |
| Smoking opium or marihuana | $500 | Same |
| Crude opium | $200 | Same |
“Opiate” takes its meaning from the Controlled Substances Act[3], so prescription opioids can fall inside it. This is guidance, not legal advice. The practical defence is a sign-on medication declaration to the master, cross-checked against the customs paperwork before arrival.
Taking prescribed medication on watch: the 33 CFR rule
On vessels inspected or subject to inspection under 46 U.S.C. chapter 33, a crew member may take a legal prescription or non-prescription drug provided it does not cause intoxication[4]. On any vessel, an operator is under the influence when the effect of an intoxicant on manner, speech, movement or behaviour is apparent by observation[5].
That second test needs no blood level. A sedating antihistamine, a sleep aid or a new opioid dose can meet it. The mariner’s prescription does not change the observation; a written medication plan agreed before sailing does reduce the chance of it happening.
A positive drug test from a legitimate prescription
Mariner drug testing follows 46 CFR part 16, conducted under the procedures in 49 CFR part 40[6]. A failed test for dangerous drugs means removal from safety duties and, for a credential holder, a report to the OCMI[6]. The medical review officer stands between the lab result and that outcome.
| MRO rule under 49 CFR 40.137[7] | What it means for the mariner |
|---|---|
| A legitimate medical explanation turns a confirmed positive into a verified negative | A valid prescription consistent with the Controlled Substances Act can clear the result |
| The MRO must not question whether the doctor should have prescribed it | The prescribing decision is not reopened |
| The burden of proof is on the employee, at the verification interview | Have the prescription details ready; the MRO may allow up to 5 days |
| Foreign medication counts only if legally obtained there, medically legitimate and used as intended | Marijuana can never be a legitimate explanation, even where legal abroad |
A cleared test is not the end of it. If the medication makes the mariner likely to be medically unqualified or a significant safety risk, the MRO may tell the employer without consent[8]. Detail on the testing program is in 46 CFR part 16 chemical testing requirements.
A crew medication policy that holds up at the gangway
Gard, the P&I club, reports “a significant number of cases” where seafarers declared fit while on medication later reported sick because their supply ran out or was poorly managed[10]. Its advice: carry enough for the whole contract, bring the prescription, and declare medication to the master on boarding[10].
- Declare at sign-on. A private form to the master or designated officer listing each medication, dose and supply[10].
- Supply for the full contract plus a margin, filled before departure where possible[10][1].
- Original containers only, with the label intact[1].
- Match the paperwork to the Crew’s Effects and any Crew Member’s Declaration before arrival[2].
- Screen for sedation. Flag drugs that could meet the observation test for safety-critical roles[4][5].
- Keep chest and personal stock separate; chest stock stays under 1301.25 control[9].
Discovery Health MD writes this policy for fleets and puts a physician behind it. Chest controlled substances run through controlled substances management, the chest itself through ship medical chest management, and the crew medication declaration and escalation plan through maritime medical consulting. Ask for a crew medication policy review before the next crew change.
Common questions
Can a seafarer bring prescription medication into a US port?
Yes, for Schedule II to V controlled medication obtained lawfully for personal use, if it stays in the original container and is declared to a customs officer with the name and schedule, or the pharmacy and prescription number[1]. See foreign-flag vessel US port medical requirements.
Is there a limit on how much medication a mariner can carry?
For US residents, 50 dosage units combined of controlled medication obtained abroad. Medication prescribed in the US by a DEA registrant is not capped by that rule[1].
Should crew medication go on the Crew’s Effects Declaration?
Articles required to be manifested and left off are subject to forfeiture, with a penalty on the master[2]. Unmanifested opiates carry $1,000 per ounce[3]. Declaring and cross-checking is the safer course.
Can a crew member stand watch on prescribed medication?
On inspected vessels, yes, if the drug does not cause intoxication[4]. On any vessel, visible impairment of speech, movement or behaviour counts as under the influence[5].
What happens if a mariner tests positive because of a prescription?
The MRO gives the mariner a chance to present a legitimate medical explanation. If it is valid, the result is verified negative[7]. The mariner carries the burden of proof[7].
Can the ship’s medicine chest supply a crew member’s regular prescription?
Chest controlled substances are distributed only to persons under the medical officer’s general supervision, except as part 1317 allows[9]. It is an emergency stock, not a pharmacy. See stocking a medicine chest.
What should a crew medication declaration include?
Each medication, dose, prescriber and supply on board, collected privately at sign-on, as Gard recommends for masters verifying medication at sign-on[10]. Container and label details support the customs declaration[1].
