Adult Dosing

Tension headache

Phrenilin

• 1-2 tabs PO q4 hrs; Max: 6 tabs/day

Phrenilin Forte

• 1 cap PO q4 hrs; Max: 6 tabs/day

Note:

• Because of the potential for physical dependence, avoid extended and long term use

Pediatric Dosing

Tension headache

• Safety and effectiveness in pediatric patients <12 yrs have not been established
• Children >12 yrs
• Phrenilin: 1-2 tabs PO q4 hrs; Max: 6 tabs/day
• Phrenilin Forte: 1 cap PO q4 hrs; Max: 6 tabs/day

Note:

• Because of the potential for physical dependence, avoid extended and long term use

[Outline]

• Adult Dosing
• Pediatric Dosing

• Relief of the symptom complex of tension (or muscle contraction) headache

• Hypersensitivity to any of the ingredients of the product
• Porphyria

• Acute liver failure, at times resulting in liver transplant and death has been reported with acetaminophen therapy, mostly associated with doses exceeding 4000 mg/day and often involve more than one acetaminophen containing product

Renal Dose Adjustment

• Renal impairment: Caution advised, dose adjustments not defined

Hepatic Dose Adjustment

• Hepatic impairment: Caution advised, dose adjustments not defined

See Supplemental Patient Information

• Extended use of butalbital is not recommended, as butalbital is habit-forming and potentially abusable
• Acute liver failure, at times resulting in liver transplant and death has been reported with acetaminophen therapy [US Black Box Warning]
• Patients with underlying liver diseases and individuals who ingest alcohol while taking acetaminophen are at higher risk of liver failure. Avoid concomitant use with any other drug containing acetaminophen
• Anaphylactic shock and other severe allergic reactions including swelling of the face, mouth, and throat, respiratory distress, urticaria, rash, pruritus, and vomiting, can occur with use of acetaminophen, before starting the treatment it should be ascertained if the patient is allergic to acetaminophen

Cautions: Use cautiously in

• Severe renal impairment
• Severe hepatic impairment
• Acute abdomen
• Alcohol abuse
• CNS depressant use
• Elderly or debilitated patients

Supplemental Patient Information

• Advise patients to avoid engaging in potentially hazardous tasks such as driving a car or operating a machinery as aspirin/butalbital/caffeine may impair the mental and/or physical abilities
• Advise patients to avoid concomitant use of alcohol and other CNS depressants
• Advise patients to take the drug only for as long as it is prescribed and in the amounts prescribed as butalbital may be habit-forming

Pregnancy Category:C

Breastfeeding: Acetaminophen is a good choice for analgesia, and fever reduction in nursing mothers. Amounts excreted in milk are much less than doses usually given to infants. Adverse effects in breastfed infants appear to be rare. This information is based upon LactMed database (available at http://toxnet.nlm.nih.gov/cgi-bin/sis/htmlgen?LACT).Maternal medication is usually compatible with breastfeeding; no observable change was seen in the nursing infant while the mother was ingesting the compound. This information is based upon data from AAP Policy Guidelines (available at http://aappolicy.aappublications.org/cgi/content/full/pediatrics;108/3/776/T6 last accessed 31 May 2011). As no published data is available with butalbital or combination products containing butalbital during breastfeeding, other agents may be preferred, especially while nursing a newborn or preterm infant. This information is based upon LactMed database (available at http://toxnet.nlm.nih.gov/cgi-bin/sis/htmlgen?LACT last accessed 31 May 2011). As per manufacturer data because of potential for serious adverse reactions in nursing infants from butalbital and acetaminophen, a decision should be made whether to discontinue nursing or to discontinue the drug, taking into account the importance of the drug to the mother.

• CNS: Drowsiness, lightheadedness, dizziness, sedation, abuse
• GI: Nausea, vomiting, abdominal pain
• RESP: Dyspnea
• HEMA: Agranulocytosis, thrombocytopenia
• DERM: Erythema multiforme, toxic epidermal necrolysis, rash
• MISC: Intoxicated feeling, allergic reactions

Acetaminophen

• Analgesic, antipyretic; increases the pain threshold by inhibiting both isoforms of cyclooxygenase, COX-1 and COX-2, enzymes involved in prostaglandin (PG) synthesis, reduces fever through direct action on hypothalamic heat-regulating center
• Rapid and almost complete absorption
• Metabolized by liver; CYP450: CYP2E1, CYP2D6
• Excreted in urine 85%
• Half-life: 1.25-3 hrs

Butalbital

• Barbiturates; act as nonselective depressants of the central nervous system (CNS), by binding at a distinct binding site associated with a Cl^-ionopore at the GABAA receptor, increasing the duration of time for which the Cl^- ionopore is open
• Well absorbed from the gastrointestinal tract
• Metabolized by liver
• Renally excreted 59-88% (3.6% unchanged)
• Half-life: 35 hrs

US Trade Name(s)

• Phrenilin
• Phrenilin Forte

US Availability

Phrenilin (acetaminophen/butalbital)

• TABS: 325 mg/50 mg

Phrenilin Forte (acetaminophen/butalbital)

• CAPS: 650 mg/50 mg

Canadian Trade Name(s)

• N/A

Canadian Availability

• N/A

UK Trade Name(s)

• N/A

UK Availability

• N/A

Australian Trade Name(s)

• N/A

Australian Availability

• N/A

[Outline]

Analgesics

Analgesics; Combinations

Pricing data from www.DrugStore.com in U.S.A.

• Phrenilin Forte 50-650 MG CAPS [Bottle] (VALEANT)
  100 mg = $557.54
  300 mg = $1589.96

Warning: This pricing information is subject to change at the sole discretion of DS Pharmacy. For the most current and up-to-date pricing information, please visit drugstore.com.

• APAP 325 MG / butalbital 50 MG Oral Tablet (MIKART, INC.)
• APAP 650 MG / butalbital 50 MG Oral Tablet (MIKART, INC.)
• Phrenilin (APAP 325 MG / butalbital 50 MG) Oral Tablet (Valeant Pharmaceuticals North America)
• Phrenilin Forte (APAP 650 MG / butalbital 50 MG) Oral Capsule (Valeant Pharmaceuticals North America)