ISOMETHEPTENE/DICHLORALPHENAZONE/ACETAMINOPHEN
| ISOMETHEPTENE/DICHLORALPHENAZONE/ACETAMINOPHEN (i-so-meth'ep-tene/di-chlor-al-phen'a-zone/a-cet'a-min-o-phen) Isopap, Duradrin, Midrin, Migratine Classifications: sympathomimetic; analgesic, nonnarcotic; Therapeutic: antimigraine; analgesic, non-narcotic Pregnancy Category: C Controlled Substance: Schedule Schedule C-IV |
Availability
65 mg
isometheptene mucate, 100 mg
dichloralphenazone, 325 mg
APAP capsules
Action
Isometheptene is a sympathomimetic amine that acts by constricting cranial and cerebral arterioles. Isometheptene relieves vascular headaches. Dichloralphenazone is a mild sedative that helps reduce headache pain. Acetaminophen is a mild analgesic.
Therapeutic Effect
Effective as a mild sedative, reduces headache pain as well as being a mild analgesic.
Uses
Relief for tension, vascular, and migraine headaches.
Contraindications
Patients with glaucoma; severe renal disease, organic heart disease; hepatic disease; concurrent MAO inhibitors; pregnancy (category C), lactation.
Cautious Use
Hypertension; peripheral vascular disease, and recent cardiovascular attacks; older adults; pulmonary disease.
Route & Dosage
| Tension Headache Adult: PO 1–2 capsules q4h up to 8 capsules/24 h Migraine Headache Adult: PO 2 capsules at onset, then 1 capsule qh until relief (max: 5 capsules/12 h) |
Administration
Oral- Do not give this drug to anyone who is concurrently using an MAOI. Allow 14 d to elapse between discontinuation of the MAOI and administration of this drug.
- Do not give more than 8 capsules in a 24 h period.
- Store at 15°–30° C (59°–86° F) in a dry place.
Adverse Effects (≥1%)
CNS: Transient dizziness. GI: Acetaminophen hepatotoxicity. Skin: Rash.Interactions
Drug: maois may cause hypertensive crisis; other acetaminophen-containing drugs (including OTC) may increase risk of hepatotoxicity.Pharmacokinetics
Absorption: Rapidly absorbed. Metabolism: Dichloralphenazone is metabolized to chloral hydrate and antipyrine. See ACETAMINOPHEN and CHLORAL HYDRATE for more detail. Elimination: Renal and hepatic. Half-Life: 12 h.Nursing Implications
Assessment & Drug Effects
- Monitor BP closely with preexisting hypertension.
- Monitor lower extremity perfusion with a history of PVD.
Patient & Family Education
- Avoid, or moderate, alcohol use while taking this drug.
- Do not drive or engage in other potentially hazardous activities until response to drug is known.
- Report any decrease in tolerance to walking if you have a history of PVD.
Common adverse effects in italic, life-threatening effects underlined; generic names in bold; classifications in SMALL CAPS; 
Canadian drug name; 
Prototype drug