Classes
DEA Class; Rx
Common Brand Names; Midrin
- Analgesics, Other Combos
Description
Isometheptene: Elicits sympathomimetic effect; constricts dilated cerebral/cranial arterioles
Dichloralphenazone: Elicits mild sedative effect; reduces emotional response to painful stimulus
Acetaminophen: Inhibitis prostaglandin sythesis in CNS and may block peripheral pain impulse generation; acts on hypothalamus to antipyresis
Indications
For the treatment of Tension Headache, Migraine Headache
Contraindications
Hypersensitivity
Hepatitis or hepatic disease
Glaucoma
Severe renal impairment
Hypertension
Peripheral vascular disease
Cardiovascular insufficiency, including recent MI or stroke
Organic heart disease
Within 14 days of taking MAO inhibitors
Adverse Effects
Rash
Transient dizziness
Warnings
Acetaminophen use is associated with rare, but serious skin reactions that can be fatal; these reactions include Stevens-Johnson Syndrome (SJS), toxic epidermal necrolysis (TEN), and acute generalized exanthematous pustulosis (AGEP); symptoms may include skin redness, blisters and rash
May increase respiratory depressant effects; caution with head injury, COPD, or other conditions with decreased respiratory drive
Controlled substance (dichloralphenazone); may cause tolerance/dependence
If therapy seems to become less effective over time, it may be a sign that the patient is becoming dependent on the medication; dose should not be increased to improve relief
If new headache occurs within 1 day after taking the medication, a headache begins to occur every day or continues for several days in a row, it may be a sign of becoming dependent on the medication; continuing therapy when this occurs may cause even more headaches over time; ask healthcare professional how to relieve the headaches
Pregnancy and Lactation
Pregnancy
Refer to individual monographs
Lactation
Refer to individual monographs
Maximum Dosage
2 capsules PO at onset of headache, then 1 capsule PO q1hr until headache relieved up to a cumulative dose of 5 capsules/12 hr
1-2 capsules PO q4hr; not to exceed 8 capsules/24 hr
Pediatric
Safety and efficacy not established
How supplied
isometheptene/dichloralphenazone/acetaminophen
capsule: Schedule IV
- 65mg/100mg/325mg