Check your passport and travel documents before you travel
If you are visiting the USA your passport should be valid for the proposed duration of your stay. You don’t need any additional period of validity on your passport beyond this.
Check with your travel provider to make sure your passport and other travel documents meet their requirements.
The US Customs and Border Protection programme Global Entry gets pre-approved travellers through border control faster at some US airports. If you’re a British citizen you can register to get a UK background check on GOV.UK. If you pass the background checks, you’ll be invited to apply for Global Entry.
UK Emergency Travel Documents
UK Emergency Travel Documents (ETDs) aren’t valid for entry into the USA or transit through the USA on an ESTA. If you’re planning to enter or transit through the USA using an ETD, you must apply for a visa from the nearest US embassy or consulate before you travel, which may take a number of days, or hold a valid lawful permanent resident card (often referred to as a ‘green card’), which you must have with you on arrival. UK ETDs issued in the USA are valid for exit from the USA.
Bringing medicines into the USA
There are restrictions and prohibitions on the import of certain prescription drugs into the US. The USA Food and Drug Administration website contains further information and advice on bringing medicines into the USA.