The NHS has told anyone taking amitriptyline to be alert to two key symptoms affecting the eyes, and to contact NHS 111 or book a doctor's appointment immediately if they suspect them. The warning covers yellowing of the whites of the eyes, eye pain, changes to sight, or swelling and redness in or around the eye.
What is amitriptyline and who takes it?
Amitriptyline is a prescription medicine mainly used to treat long-term pain, including nerve pain, and to help prevent migraines. It comes as tablets or as a liquid that is swallowed. It can also be used to treat depression, though the dose for pain is usually much lower.
Because the doses used for pain are lower than those used for depression, side effects are usually milder and often settle within a few days, the NHS explains. Many common side effects improve as the body gets used to the medicine, but it is still important to know the warning signs that may mean a doctor's advice is needed.
Common side effects to expect
Common side effects, which happen in more than 1 in 100 people, include constipation, feeling dizzy, a dry mouth, feeling sleepy or tired, difficulty peeing, and headache. The NHS suggests there are things people can do to help cope with these effects.
Serious side effects and when to seek urgent help
Serious side effects are rare, the NHS stresses, but some people can experience them. A doctor or NHS 111 should be called if there is a fast or irregular heartbeat, yellowing of the whites of the eyes or skin (which may be less obvious on brown or black skin) as these can be signs of a liver problem, or a headache with confusion, weakness, or muscle cramps, which can be signs of a low sodium level in the blood. Eye pain, a change in eyesight, or swelling or redness in or around the eye also warrant a call to 111.
Call 999 if there is weakness on one side of the body, trouble speaking or thinking, loss of balance, or blurred eyesight – these can be signs of a stroke. A seizure or fit, or severe chest pain, which can be a sign of a heart attack, also require 999. The NHS advises not to drive yourself to A&E; instead, call 999 and the operator will advise what to do next. The NHS also stresses that 999 or A&E should be used if there are thoughts about harming yourself or ending your life.
Serious allergic reaction
In rare cases, it is possible to have a serious allergic reaction (anaphylaxis) to amitriptyline. Call 999 if the lips, mouth, throat or tongue suddenly become swollen; if breathing becomes very fast or difficult, with wheezing or choking; if the throat feels tight or swallowing is difficult; if the skin, tongue or lips turn blue, grey or pale (on black or brown skin, this may be easier to see on the palms or soles); if sudden confusion, drowsiness or dizziness occurs; if someone faints and cannot be woken; or if a child becomes limp, floppy or unresponsive. A rash that is swollen, raised, itchy, blistered or peeling may also appear.
The NHS adds: "These are not all the side effects of amitriptyline. For a full list see the leaflet inside your medicine packet." Suspected side effects can be reported using the Yellow Card safety scheme, with more information available on the Yellow Card website.
