Who should not have anti-wrinkle injections at all?
Two reasons are written into the product information as contraindications. The first is known hypersensitivity to any botulinum toxin preparation or to any ingredient in the formulation. The second is infection at the proposed injection site. Everything else on this page is either a condition that needs extra caution, a situation where there is no adequate evidence, or a reason to wait.
A note on the source: the figures below come from the prescribing information for BOTOX Cosmetic (onabotulinumtoxinA), the product most people mean by Botox. Other registered botulinum toxin products have their own labels with their own wording, so the product being used matters, and a doctor should be able to tell you which it is.
Can you have anti-wrinkle injections when pregnant or breastfeeding?
It is generally not advised, and the reason is a gap in the data, not a proven harm. The label says there are no studies or adequate data from postmarketing surveillance on the developmental risk in pregnant women, and that animal studies showed reduced fetal body weight and skeletal ossification at clinically relevant doses, in the presence of maternal toxicity. For breastfeeding, it says there are no data on the presence of the toxin in milk, on the effects on a breastfed child, or on milk production.
A 2016 report from the manufacturer's safety database gives some context. It held 574 pregnancies with exposure to onabotulinumtoxinA before or during pregnancy, mostly in the first trimester, and 232 had known outcomes. Among 137 prospective cases, 79.1 per cent ended in a live birth and 20.9 per cent in fetal loss, and fetal defects occurred in 2.7 per cent of live births (3 of 110), which the authors consider comparable with background rates. These are spontaneous reports and not a controlled study, so they cannot show that exposure is safe. The longer discussion, including what can wait and what the labels of fillers say, is in aesthetic treatments in pregnancy.
Which nerve and muscle conditions make toxin unsuitable?
The label warns that people with neuromuscular disorders may be at increased risk of clinically significant effects, including generalised muscle weakness, double vision, drooping eyelids, voice and speech changes, severe difficulty swallowing and respiratory compromise. It names peripheral motor neuropathic disease, amyotrophic lateral sclerosis and neuromuscular junction disorders such as myasthenia gravis and Lambert-Eaton syndrome, and says these people should be monitored when given botulinum toxin.
The reason is the mechanism. The toxin works by blocking the signal between nerve and muscle, and these conditions already weaken that signal. A cosmetic dose is small, but a small effect added to a weak signal can matter. The practical point is to mention any nerve or muscle condition, past or present, before any injection, even one you consider unrelated.
Which medicines and allergies matter?
On medicines, the label singles out aminoglycosides (a class of antibiotics) and other agents that interfere with neuromuscular transmission, such as curare-like compounds, and says combining them with the toxin should be done only with caution because the effect of the toxin may be potentiated. Your doctor needs your full medicine list, including recent antibiotic courses. Blood thinners, fish oil and herbal products raise a different issue, bruising, which is covered in the article on blood thinners and supplements before injections.
On allergy, the label contraindicates known hypersensitivity to any botulinum toxin preparation or any component, and it lists serious hypersensitivity reactions, including anaphylaxis, among the warnings. The product contains human albumin, so a known allergy to albumin is relevant; the label also notes a remote theoretical risk of transmitting viral disease from this blood-derived ingredient, with no cases identified. If you have reacted to a toxin product before, say so.
Why does a doctor sometimes say "not yet"?
Because the treatment may be suitable and the moment is not. The label contraindicates infection at the injection site and advises caution with inflammation there, so a skin infection, a flare of inflammation or an unhealed area is a reason to wait until it settles. A recent unwell spell, or a planned procedure nearby, is for the doctor to weigh.
Bruising is another. If a medicine or supplement raises the chance of a bruise, the plan may be to sort that out first, as the blood thinner article explains. And the label states that the safety and effectiveness of dosing more often than every three months have not been clinically evaluated, so a request for a repeat dose soon after a treatment is a reason to hold off.
What if an event is coming up?
Timing is a legitimate reason for "not yet", because the effect is not instant. In the label's glabellar line trials, the investigator rated 74 per cent of treated people as responders at Day 7 and 80 per cent at Day 30, against 6 and 3 per cent on placebo, so the effect continues to build over the first weeks. Those are trial figures and not a prediction for any one face.
The practical reading is that a treatment booked days before a wedding leaves no time to see how the face settles or to adjust anything. The article on how far ahead to plan before an event sets out the published timelines for toxin, filler and HydraFacial.
Can eyelid or brow position make toxin a poor idea?
Yes, because toxin relaxes muscles that hold the brow and lid up as well as ones that draw them down. The label advises caution when there is existing ptosis (a drooping eyelid) or excessive weakness of the target muscle. In the label's trials, eyelid ptosis was reported in 3 per cent of people treated for frown lines, and brow ptosis in 2 per cent of those treated for forehead lines.
A brow that already sits low, a heavy upper lid, or a forehead that is doing the work of holding the eye open may mean the plan changes: a lower dose, a different pattern, or a different treatment. A droop after treatment is usually temporary; the article on droopy eyelids after Botox covers what it is and how long it lasts, and the page on anti-wrinkle injection side effects sets the rest of the risks in context.
What about body dysmorphic concerns and unrealistic expectations?
Anti-wrinkle injections soften lines made by muscle movement. They do not change bone, volume, skin quality or a feature that someone finds distressing out of proportion to how it looks to others. When the goal is something the treatment cannot do, the result will disappoint however well it is done.
Body dysmorphic disorder is a preoccupation with perceived defects in appearance that causes distress. A 2025 systematic review and meta-analysis reported a prevalence of 17 per cent in the general population and 24 per cent in plastic surgery patients, and linked the disorder to disappointment with cosmetic treatments (figures as given in the abstract). A doctor cannot diagnose this from a conversation about a frown line, but a sound approach is to ask what the person hopes will change, to be willing to say that injections will not do that, and to suggest a conversation with a GP or mental health professional when the worry seems larger than the feature. That is a duty of care and not a verdict on anyone.
What does "not yet" mean in practice?
It means a plan with a reason and a way back. The reason might be an infection to clear, a medicine to review, a bruise risk to manage, an event to plan around, or a question about what the treatment can realistically change. The way back is a point at which the question is asked again. It does not mean the answer is always no.
The page on anti-wrinkle injections sets out what the treatment does. This article is the other half: the cases in which the right answer from a doctor is no, or not yet, and why.
