Headache

Question 0

Sumatriptan (Imitrex), Triptans

Answer 0

Class: 5HT1b (blood vessel) and 5HT1d (neuron) agonists, vasoconstrictor, anti-headache, serotonin with an amino-ethyl group and a sulfonamide group
Indication: migraine, acute cluster headache (O2 can also be given, IN lidocaine, zolmitriptan, IV ergots)
PK: efficacy 60-80% at 2h, 40% recurrence in 24h
ADR: chest/neck tightness, flushing, sedation
Contraindication: CAD, stroke
Interaction: with SSRI/SNRI (serotonin syndrome, controversial), with MAOIs, rizatriptan levels are increased by propanolol, eletriptan, and to a lesser degree zolmitriptan, are metabolized by the cytochrome P450 system.

Question 1

Ergotamine, Dihydroergotamine (DHE)

Answer 1

Class: agonist at 5HT1b and 1d receptors, anti-migraine, vasoconstrictor
MOA: broad range of receptor activation, serotonin, adrenergic, dopaminergic, suppress neurogenic inflammation
PK: DHE with 10 hour half-life, used mainly in iv, im, in.
Special: avoid in CAD (due to vasoconstriction), category X in pregnancy, narrow therapeutic window (n/v)

Question 2

Prophylactic Headache Rx

Answer 2

When to use preventative management: significantly interfere with pt’s daily routine, acute medications contraindicated, intolerable ADR, overused, frequent h/a (>2 attacks per week), uncommon migraine conditions, cost consideration, patient preference

1. Propanolol, timolol: good if MVP, HTN, anxiety, tremor, bad if depression, Raynaud’s, fibromyalgia, asthma, initiate dosing propanolol 10-20mg tid, monitor pulse and BP
2. Amitriptyline (TCA), inhibits presynaptic reuptake of serotonin, NE, blocks M, H1, a1, 5HT2 receptors, ADR includes weight gain, sedation, dry mouth, orthostatic hypotension, arrhythmia, good if sleep disturbance, neck pain, TTH, watch QTc on EKG
3. Topiramate: usually bid, reduces firing of neurons in the TNC, ADR includes weight loss, cognitive difficulty, acute glaucoma, nephrolithiasis, paresthesia
4. Valproic acid: enhances GABA activity, reduces excitatory neurotransmission, reduces firing rate of midbrain 5-HT neurons, extended release formulation, lower doses than for epilepsy, efficacy doesn’t correlate with blood levels, approx 1% risk of spina bifida
5. Verapamil, Botox for migraine prophylaxis
6. Verapamil, Methysergide, Steroids for cluster h/a prophylaxis

Question 3

Non-pharmacologic Tx

Answer 3

Relaxation training, thermal biofeedback with relaxation training, EMG biofeedback, CBT
Consider for pregnant pts, lactating pte

Question 4

NSAID

Answer 4

First line for tension-type h/a;

for chronic tension-type h/a, behavioral modalities, amitriptylaine are indicated, NSAID is unproven and carries risks