421 Pill — GREEN ROUND, 10mm — Phenobarbital

Imprint	421
Colour	GREEN
Shape	ROUND
Size	10
Strength	Phenobarbital 48.6 mg;HYOSCYAMINE SULFATE 0.3111 mg;ATROPINE SULFATE 0.0582 mg;SCOPOLAMINE HYDROBROMIDE 0.0195 mg
Dosage form	Tablet, Film Coated, Extended Release
Manufacturer	PBM Pharmaceuticals, Inc
NDC	66213-421
Schedule	—
Availability	—
Ingredients	Phenobarbital[Phenobarbital];HYOSCYAMINE SULFATE[HYOSCYAMINE];ATROPINE SULFATE[ATROPINE];SCOPOLAMINE HYDROBROMIDE[SCOPOLAMINE]

What does this imprint mean?

The imprint "421" is a code stamped or printed on the tablet or capsule by the manufacturer, used to identify the drug, its strength and the maker.

Active ingredient

Phenobarbital

Uses and warnings

BOXED WARNING: "MAY BE HABIT-FORMING." The label states "tolerance and psychological and physical dependence may occur with continued use," and that "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." Prescribing and dispensing should be "limited to the amount required for the interval until the next appointment." As a CNS depressant, the label warns that "the concomitant use of alcohol or other CNS depressants may produce additive CNS depressant effects" - a category that includes opioid analgesics, raising the risk of profound sedation and respiratory depression when combined. The label also warns that "barbiturates can cause fetal damage when administered to a pregnant woman."

Indicated as a sedative, and "for the treatment of generalized and partial seizures," including generalized tonic-clonic (grand mal) and cortical focal seizures; also used for short-term sedation of anxiety and tension.

Read the full drug profile →

How to identify this pill

• Check the imprint matches exactly: "421".
• Confirm the colour (GREEN) and shape (ROUND).
• Compare the size (10) against a ruler if possible.
• When in doubt, confirm with a pharmacist before taking any medication.

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CIBA 3

GREEN ROUND · Methylphenidate