OTCs Today
Daniel L. Krinsky, RPh, MS
Headaches resulting from tension (stress), diagnosed migraine, sinus, and analgesic overuse are the most common and amenable to self-treatment. Headaches generally are classified as primary or secondary. Approximately 90% are primary, meaning they are not associated with an underlying illness.
Nonprescription self-treatment options
The goals of treating headache are to reduce the severity and alleviate acute pain, restore normal functioning, prevent relapse, and minimize adverse effects. Many headache sufferers self-treat with nonprescription products rather than seek medical attention; as much as two-thirds of nonprescription analgesic use is attributed to headache.
Nonprescription analgesics are useful for treating headache, either as monotherapy or as adjuncts to nonpharmacologic or prescription therapy. Available nonprescription analgesics include acetaminophen, the NSAIDs ibuprofen and naproxen, and the salicylates aspirin and magnesium salicylate. Frequency of use should be limited to less than 3 days per week to prevent medication-overuse headache.
Acetaminophen. Acetaminophen produces analgesia through central inhibition of prostaglandin synthesis. FDA has required manufacturers to include a boxed warning on acetaminophen products that addresses its potential to cause hepatotoxicity in doses exceeding 4 g per day. Caution patients not to exceed the dose limit or to use when consuming alcoholic beverages. Acetaminophen may cause severe skin reactions such as skin reddening, blisters, and rash.
OTC NSAIDs. NSAIDs relieve pain through central and peripheral inhibition of COX with consequent inhibition of prostaglandin synthesis. The most frequent adverse effects involve the GI tract and include dyspepsia, heartburn, nausea, anorexia, and epigastric pain. NSAIDs may be taken with food, milk, or antacids if upset stomach occurs. NSAID use is associated with increased risk for bleeding, myocardial infarction, heart failure, hypertension, and stroke.
Salicylates. Salicylates inhibit prostaglandin synthesis from arachidonic acid by inhibiting both isoforms of the COX enzyme (COX-1 and COX-2). Aspirin is known to cause various GI adverse effects. Enteric coating may decrease local gastric irritation. However, with regard to the risk of major GI ulceration and bleeding, no difference has been identified among plain, enteric-coated, and buffered products.
A significant concern about aspirin consumption is the development of Reye’s syndrome, an acute illness occurring almost exclusively in children and teenagers. Aspirin and other salicylates (including bismuth subsalicylate and nonaspirin salicylates) should be avoided in children and teenagers who have influenza or chickenpox.
Clinically important drug interactions are possible with all OTC analgesics. Clinicians should obtain an updated comprehensive list of medications from patients before recommending any product. Children 2 years and older may use acetaminophen or ibuprofen. Children 12 years and older may use naproxen. Acetaminophen is generally recognized as the agent of choice to manage mild to moderate pain in the geriatric population.
Key exclusions for self-treatment are severe head pain, headaches that persist for 10 days with or without treatment, secondary headache, and children younger than 8 years.
Analgesic use during pregnancy and breastfeeding
Acetaminophen is considered safe for use during pregnancy and breastfeeding. NSAID use is contraindicated during the third trimester of pregnancy because all potent prostaglandin synthesis inhibitors can cause delayed parturition, prolonged labor, and increased postpartum bleeding. NSAID use during pregnancy should be limited to clinical situations in which the potential benefit justifies potential risk to the fetus. Nursing mothers should not use naproxen. Aspirin should be avoided during pregnancy, especially during the last trimester, and during breastfeeding.
Counseling tips
Explain to your patients the appropriate drug and nondrug measures for treating headaches. Remind patients to take an appropriate dose of analgesic early in the course of the headache. Encourage patients for whom headache is a relatively common occurrence to keep a log of their headaches to document triggers, frequency, intensity, duration of episodes, and response to treatment.