Grapefruit juice interactions with drugs
Article Abstract:
Grapefruit juice may inhibit the metabolism of some drugs in the body. Naringenin, a human metabolite of naringin responsible for the bitter flavor in grapefruits, is thought to block early, presystemic metabolism. P450 isozymes are involved but the precise mechanisms need to be determined. Researchers noted increased blood concentrations of several calcium-channel blockers after patients drank grapefruit juice. It is possible that larger amounts of drugs enter the system without being metabolized. Grapefruit juice seems to also block the isozyme CYP1A2 which normally processes caffeine. Orange juice seems to have no such effect. Further studies may clarify the nature benefit of these metabolic changes due to grapefruit juice.
Publication Name: Medical Letter on Drugs and Therapeutics
Subject: Health
ISSN: 0025-732X
Year: 1995
User Contributions:
Comment about this article or add new information about this topic:
Drugs past their expiration date
Article Abstract:
It may be safe to use drugs beyond their original expiration date, usually two years from the date of manufacture. Potency losses may be minimal up to one or two years after the package was opened. Humidity and other storage conditions may adversely affect drug potency, however. Unopened drugs stored under average conditions may retain 70% to 80% of their potency for at least 10 years. Exposure to the elements will quickly deteriorate nitroglycerin and paraldehyde, the exceptions to the rule.
Publication Name: Medical Letter on Drugs and Therapeutics
Subject: Health
ISSN: 0025-732X
Year: 1996
User Contributions:
Comment about this article or add new information about this topic:
Generic drugs
Article Abstract:
Most generic versions of brand-name drugs are equivalent to the brand-name drug and there have been no reports of treatment failures while using generic drugs. Generic drugs are created when the patent on a brand-name drug expires. Many doctors do not prescribe generic drugs because they believe the drug is not equivalent to the brand-name drug. All generic drugs must be approved by the FDA and must be documented to be equivalent to the brand-name version.
Publication Name: Medical Letter on Drugs and Therapeutics
Subject: Health
ISSN: 0025-732X
Year: 1999
User Contributions:
Comment about this article or add new information about this topic:
- Abstracts: Transference phenomena in medical practice: being whom the patient needs. The Charter on Medical Professionalism and the limits of medical power
- Abstracts: Safety training goes interactive. Boom in older workers goes international
- Abstracts: Claudification: stepping out of the poor circulation problem. Leg ulcers: veins are the problem more than half of the time
- Abstracts: A plan for action to reduce hospital-acquired infection. Planning for pediatric laceration repairs. Do episiotomies reduce risk of laceration?
- Abstracts: Relief work. Findings of a national survey of acute pain services. Clinical staff knowledge of acute pain relief