Acetaminophen and pamabrom

Acetaminophen and pamabrom: Drug information
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(For additional information see “Acetaminophen and pamabrom: Patient drug information”)

Brand Names: U.S. Cramp Tabs [OTC], Midol® Teen Formula [OTC], Tylenol® Women’s Menstrual Relief [OTC]
Pharmacologic Category Analgesic, Miscellaneous; Diuretic, Combination
Dosing: Adult Menstrual symptoms: Oral: Acetaminophen 650-1000 mg and pamabrom 50 mg every 4-6 hours as needed (maximum: 8 caplets/tablets/24 hours)
Dosing: Pediatric Children ≥12 years: Refer to adult dosing.
Dosage Forms: U.S. Excipient information presented when available (limited, particularly for generics); consult specific product labeling.
Caplet:

Midol® Teen Formula: Acetaminophen 500 mg and pamabrom 25 mg

Tylenol® Women’s Menstrual Relief: Acetaminophen 500 mg and pamabrom 25 mg

Tablet:

Cramp Tabs: Acetaminophen 325 mg and pamabrom 25 mg

Generic Equivalent Available: U.S. Yes
Use Temporary relief of symptoms associated with premenstrual and menstrual symptoms (eg, cramps, bloating, water-weight gain, headache, backache, muscle aches)
Medication Safety Issues
Other safety concerns:
Duplicate therapy issues: This product contains acetaminophen, which may be a component of other combination products. Do not exceed the maximum recommended daily dose of acetaminophen.

Adverse Reactions Significant See Acetaminophen monograph.
Warnings/Precautions
Concerns related to adverse effects:

• Hepatotoxicity: Acetaminophen may cause hepatic toxicity with acute overdose; in addition chronic daily dosing has resulted in liver damage in some adults.

• Hypersensitivity: Discontinue use if hypersensitivity occurs.

Disease-related concerns:

• Ethanol use: Use with caution in patients with alcoholic liver disease; consuming ≥3 alcoholic drinks/day may increase the risk of liver damage.

Special populations:

• Pediatrics: Not for use in children <12 years of age.

Other warnings/precautions:

• Dosage limit: Limit acetaminophen dose to <4 g/day in adults.

• Self-medication (OTC use): Should not be used with other products containing acetaminophen. Patients should be instructed to contact healthcare provider if new symptoms occur, if redness or swelling occurs, or pain lasting >10 days.

Drug Interactions
(For additional information: Launch Lexi-Interact™ Drug Interactions Program )
Anticonvulsants (Hydantoin): May increase the metabolism of Acetaminophen. This may 1) diminish the effect of acetaminophen; and 2) increase the risk of liver damage. Risk C: Monitor therapy

Barbiturates: May increase the metabolism of Acetaminophen. This may 1) diminish the effect of acetaminophen; and 2) increase the risk of liver damage. Risk C: Monitor therapy

CarBAMazepine: May increase the metabolism of Acetaminophen. This may 1) diminish the effect of acetaminophen; and 2) increase the risk of liver damage. Risk C: Monitor therapy

Cholestyramine Resin: May decrease the absorption of Acetaminophen. Effect is minimal if cholestyramine is administered 1 hour after acetaminophen. Risk D: Consider therapy modification

Conivaptan: May increase the serum concentration of CYP3A4 Substrates (Low risk). Risk C: Monitor therapy

Cyproterone: May decrease the serum concentration of CYP1A2 Substrates. Risk C: Monitor therapy

Cyproterone: May decrease the serum concentration of CYP2E1 Substrates. Risk C: Monitor therapy

Dasatinib: Acetaminophen may enhance the hepatotoxic effect of Dasatinib. Dasatinib may increase the serum concentration of Acetaminophen. Risk D: Consider therapy modification

Imatinib: Acetaminophen may enhance the hepatotoxic effect of Imatinib. Imatinib may increase the serum concentration of Acetaminophen. Risk D: Consider therapy modification

Isoniazid: May enhance the adverse/toxic effect of Acetaminophen. Risk C: Monitor therapy

Metyrapone: May increase the serum concentration of Acetaminophen. More importantly, by inhibiting the conjugative metabolism of acetaminophen, metyrapone may shift the metabolism towards the oxidative route that produces a hepatotoxic metabolite. Risk C: Monitor therapy

Peginterferon Alfa-2b: May decrease the serum concentration of CYP2D6 Substrates. Risk C: Monitor therapy

Probenecid: May increase the serum concentration of Acetaminophen. Probenecid may also limit the formation of at least one major non-toxic metabolite, possibly increasing the potential for formation of the toxic NAPQI metabolite. Risk D: Consider therapy modification

SORAfenib: Acetaminophen may enhance the hepatotoxic effect of SORAfenib. SORAfenib may increase the serum concentration of Acetaminophen. Risk D: Consider therapy modification

Tocilizumab: May decrease the serum concentration of CYP3A4 Substrates. Risk C: Monitor therapy

Vitamin K Antagonists (eg, warfarin): Acetaminophen may enhance the anticoagulant effect of Vitamin K Antagonists. Most likely with daily acetaminophen doses >1.3 g for >1 week. Risk C: Monitor therapy

Ethanol/Nutrition/Herb Interactions Ethanol: Excessive intake of ethanol may increase the risk of acetaminophen-induced hepatotoxicity. Avoid ethanol or limit to <3 drinks/day.

 

REFERENCES
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