Side effects: what to expect and when to get help – manual

Most men get on with treatment without much trouble, and the side effects that do show up are usually mild and settle as your body adjusts. This page covers what is common, what is worth telling us about, and the things that should not wait.

What is common in the first few weeks

Some pain, redness or bruising where you inject.
Mild acne or oilier skin.
Mild mood changes. These are most common in the first weeks.
Hot flushes or night sweats, most common in the first three to four weeks.
A change in sex drive, up or down, in the early weeks.
Mild fluid retention.
Tenderness or sensitivity around the nipples.
Your testicles may become smaller while you are on treatment.

Things to tell us about

These are not emergencies, but a doctor should look at them, and there is often something straightforward we can do — adjusting your dose, splitting it into smaller more frequent doses, or adding another medicine:

Mood changes that last more than two weeks.
Hot flushes that are frequent and carry on for more than a week.
Acne that is severe, or that is still there after three months.
Nipple tenderness that lasts more than six weeks, or breast tissue that is swelling.
Snoring with daytime tiredness, which can be a sign of sleep apnoea.
Headaches that have started since you began treatment.
Hair thinning or hair loss.
A high blood pressure reading, if you measure it at home.
A change in sex drive or erections that is still bothering you after four weeks.
Fluid retention that is still there after four weeks.
A change in how often or how urgently you need to pass urine, or in your stream.

Message our clinicians through your account, or email us at trt@manual.co. It does not cost anything to ask.

Call 999 or go to A&E now if you have

Please do not wait to hear back from us for any of these. Get emergency help first, and tell us afterwards so your doctor knows.

Chest pain or pressure, or breathlessness while you are resting — or a racing or pounding heart alongside either.
Fainting or blacking out.
Sudden weakness or numbness in your face, arm or leg, a drooping face, slurred or changed speech, sudden changes to your vision, trouble walking or keeping your balance, or new confusion or drowsiness.
A tight throat, swelling of your lips or face, hives, gasping, or struggling to speak a full sentence.
Coughing up blood.
Blood in your vomit or stools, or signs of dehydration such as passing much less urine or feeling faint.
Sudden severe pain in a testicle.
Sudden loss of vision in one or both eyes. Tell us as well, so a doctor can review your treatment, and if you take Clomid tablets stop them.
A blood pressure reading of 180/120 or higher.

If you feel unsafe or have thoughts of harming yourself, get help now: call 999 or go to A&E if you are in immediate danger, or call 111 and choose option 2, or speak to your GP. The Samaritans are on 116 123, free, day or night.

Get medical help the same day — call 111 or your GP — if you have

A headache that keeps getting worse, wakes you at night, is there as soon as you wake, is worse when you cough, sneeze or bend down, or comes with being sick — or one that will not shift with paracetamol or ibuprofen.
Hot flushes together with a headache, blurred vision or dizziness.
Pain, redness or swelling in one or both legs.
Blood in your urine or semen.
Severe eye pain, or being unable to open or move an eye. If you take Clomid tablets, stop them and tell us.
Dizziness that is not going away.
Vomiting or diarrhoea that goes on for more than a week.
Severe weight gain, or swollen legs with breathlessness.
A lump on one side of your chest, or discharge from a nipple.

Anything that feels severe or frightening is worth acting on, even if it is not on these lists. If you are unsure how urgent something is, 111 can tell you.

Your injection site

A little soreness, redness or bruising afterwards is normal. What is not normal is an area that is spreading or hot to the touch, pus coming from the site, a temperature above 38°C, or shivering with a fever. That can mean an infection: do not take your next dose, and get medical help the same day.

If injecting is uncomfortable or you are unsure of your technique, ask us — we can send you the tutorial videos or book you an injection training call.

Oestrogen-related effects

Testosterone partly converts to oestrogen, and for some men that rises higher than we would like. It is one of the things your blood tests watch. Signs to look out for are breast tissue developing or tenderness, feeling unusually emotional, low mood or low energy, a drop in sex drive, or gaining fat around the stomach, hips and buttocks. Tell us if you notice these: a doctor can adjust your dose, split it into smaller doses, change your HCG dose if you are on it, or prescribe a medicine that reduces the conversion.

What your blood tests are watching

Alongside your testosterone levels, your monitoring tests check things that treatment can affect, including how thick your blood is, your oestrogen, your prostate marker, and your liver and kidney function. This is the main reason monitoring tests matter: most problems show up there before you would notice anything, and your doctor can act early.

Stopping or changing your treatment

Please do not change your dose on your own. If a side effect means your treatment needs to pause or change, your doctor will tell you and will decide when to start again.

There are two exceptions where you should hold your next dose straight away and tell us: signs of an injection-site infection or an allergic reaction, and any of the heart symptoms or a blood pressure reading of 180/120 or higher. If you have injected more than you were prescribed, do not inject again and message us — and use the emergency advice above if you feel unwell.