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Chemo week 1 side effects: what the first week often looks like
By Cura Editorial Team ·
This post is part of our chemo series. For the full cycle at a glance, start with chemo side effects week by week.
Infusion day
Many people are surprised that the treatment day itself feels calm. You may spend a few hours in a chair while medicines run through an IV or a port. The team usually gives medicines before the chemo to help prevent nausea and reactions.
Things people often notice on infusion day:
- Feeling tired from the long day and the waiting
- A cold feeling in the arm during some infusions
- A metallic taste
- Feeling fine, which is common and nothing to worry about
Bringing a water bottle, a snack your team says is fine, a warm layer, and something to pass the time can make the day easier.
The steroid window
Many regimens include a steroid on infusion day and sometimes for a day or two after. Steroids can make some people feel unusually energetic, hungry, flushed, or unable to sleep. This can last one to three days.
It is easy to overdo things during this window because you feel better than expected. Many people find it helps to keep plans light, even when energy feels high.
The first crash
As the steroid effect wears off, many people feel a drop in energy, often somewhere around days 3 to 5. People describe it as heavy tiredness that sleep does not fully fix. Taste changes, a dry mouth, mild nausea, or bowel changes may also show up.
Not everyone has a crash, and the timing differs by treatment. Ask your care team what is typical for your regimen.
What to track in week 1
A simple log helps you and your care team see your pattern. Many people track:
- Temperature, at the times your team suggests
- Nausea, and when it starts or eases
- Energy on a simple 1 to 10 scale
- Bowel movements, including constipation or diarrhea
- How much you are eating and drinking
- Any new pain, rash, or mouth soreness
Bring the log to your next visit. Patterns from cycle 1 often help the team adjust support for cycle 2.
When to call the care team
Your team will give you specific instructions and a number to call, including after hours. Many teams ask you to call right away for:
- A temperature of 100.4°F (38°C) or higher, or the number your team gave you
- Shaking chills
- Vomiting or diarrhea that will not stop, or not being able to keep fluids down
- Signs of dehydration, such as dizziness or very little urine
- New shortness of breath, chest pain, or swelling
- Redness, swelling, or pain around your IV or port site
If something feels wrong and you are not sure, calling is the right choice. For emergencies, call 911.
Keep reading the series
Sources
Hope
Steady, plain language notes for the days you are waiting on results or going through treatment.
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This information is for general educational purposes and isn't a substitute for advice from your own care team. Cura Well Plan does not provide medical advice, diagnosis, or treatment, and AI-generated content may contain errors — always confirm important details with a qualified healthcare provider. If you're experiencing a medical emergency, contact emergency services immediately.