Suvo

Indications

Suvorexant is used to treat insomnia in adults who have difficulty falling asleep and/or staying asleep.

How It Works

Suvorexant is an orexin receptor antagonist. Orexins are brain chemicals that keep you awake and alert. By blocking orexin receptors (OX1R and OX2R), Suvorexant turns down the wake signal so that sleep can start and continue, rather than sedating the whole brain like many older sleeping pills.

Dosage and Administration

The usual adult starting dose is 10 mg once a night, taken within 30 minutes of going to bed, and only if you have at least 7 hours left before you plan to wake up, or as prescribed. The maximum is 20 mg once a night. It may work more slowly if taken with or soon after a meal. Take no more than one dose per night. Lower doses are used with some interacting medicines.

Interactions

• Strong CYP3A4 inhibitors (Ketoconazole, Itraconazole, Clarithromycin, Ritonavir): not recommended together.
• Moderate CYP3A4 inhibitors (Fluconazole, Erythromycin, Diltiazem, Verapamil, grapefruit juice): a lower dose is used.
• CYP3A4 inducers (Rifampicin, Carbamazepine, Phenytoin): reduce its effect.
• Alcohol, opioids, benzodiazepines, other sleeping pills, antihistamines and other CNS depressants: increased drowsiness and impairment; avoid alcohol.
• Digoxin: levels may rise; monitoring may be needed.

Contraindications

• Narcolepsy.
• Allergy to Suvorexant or any ingredient.

Side Effects

The most common effect is next-day drowsiness. Others include headache, dizziness, abnormal dreams, dry mouth and tiredness. Less often, it may cause sleep paralysis (being briefly unable to move or speak when falling asleep or waking), hallucinations at sleep onset, or brief leg weakness.

Get urgent medical help, or stop and contact your doctor, if you or others notice complex sleep behaviours (such as sleep-walking, sleep-driving or cooking while not fully awake), new or worsening depression or thoughts of suicide, unusual behaviour changes, or signs of a severe allergic reaction.

Pregnancy and Lactation

There is little information on use in pregnancy; use only if your doctor thinks the benefit outweighs the risk. It is not known if it passes into breast milk. If you breastfeed, watch your baby for excess sleepiness and ask your doctor.

Precautions and Warnings

Do not drive or do activities requiring full alertness the next day if you do not feel fully awake, especially at 20 mg. Use with care in people with breathing problems such as COPD or sleep apnoea, severe liver disease, a history of depression or substance misuse. If insomnia does not improve after 7 to 10 days, see your doctor, as there may be another cause. It may be a controlled medicine; keep it secure.

Overdose

Overdose may cause severe drowsiness and confusion. Seek emergency medical help, especially if other sedatives or alcohol were also taken.

Therapeutic Class

Hypnotic (sleep medicine), dual orexin receptor antagonist.

Storage

Store below 30°C in a dry place, away from light and out of the reach of children.