Three Saxenda pens will last you 18 days at the full maintenance dose of 3.0 mg per day. If you’re still in the dose escalation phase, they’ll stretch significantly longer, potentially covering about four and a half weeks. The difference comes down to how much medication you’re injecting each day.
What’s Inside Each Pen
Every Saxenda pen contains 18 mg of liraglutide in 3 mL of solution. Three pens give you 54 mg total. How quickly you use that supply depends entirely on where you are in the dosing schedule. At the lowest starting dose, each pen lasts 30 days. At the highest maintenance dose, each pen lasts just 6 days.
The Dose Escalation Timeline
Saxenda doesn’t start at full strength. You increase your dose weekly over five weeks to help your body adjust and reduce nausea:
- Week 1: 0.6 mg per day (uses 4.2 mg per week)
- Week 2: 1.2 mg per day (uses 8.4 mg per week)
- Week 3: 1.8 mg per day (uses 12.6 mg per week)
- Week 4: 2.4 mg per day (uses 16.8 mg per week)
- Week 5 onward: 3.0 mg per day (uses 21.0 mg per week)
If you’re starting Saxenda for the first time with three pens, your 54 mg of total medication will carry you through the first four full weeks of escalation (42 mg used) and about four days into week five. That’s roughly 32 days.
At the Full 3.0 mg Dose
Once you reach maintenance, the math is straightforward. Each pen holds 18 mg, and you inject 3.0 mg daily, so one pen lasts exactly 6 days. Three pens cover 18 days. That’s less than three weeks, which catches many people off guard when they’re budgeting or timing prescription refills.
A standard Saxenda prescription box comes with five pens (90 mg total), which lasts 30 days at the maintenance dose. Three pens represent just over half a month’s supply at full dose. If you’re receiving three pens as a partial fill or starter supply, plan your refill well before you run out, since gaps in treatment can affect your progress.
How Long Each Pen Lasts by Dose
Here’s a quick reference for one pen at each dose level:
- 0.6 mg/day: 30 days per pen
- 1.2 mg/day: 15 days per pen
- 1.8 mg/day: 10 days per pen
- 2.4 mg/day: 7.5 days per pen (you’ll finish partway through day 8)
- 3.0 mg/day: 6 days per pen
Multiply any of these by three to get your answer for three pens. At the 1.8 mg dose, for example, three pens last a full 30 days.
The 30-Day Shelf Life Rule
Once you use a Saxenda pen for the first time, it stays effective for 30 days whether stored at room temperature or in the refrigerator. After 30 days, you need to discard it even if medication remains inside. This usually isn’t a concern at higher doses since you’ll empty a pen in under two weeks. But at lower doses during escalation, a single pen can technically last 30 days, right at the stability limit. Don’t let an opened pen sit unused beyond that window.
Unopened pens should stay refrigerated until you’re ready to use them. Keep them between 36°F and 46°F (2°C to 8°C) and check the expiration date on the box.
What to Do if You Miss a Dose
Missing a dose won’t ruin your progress, but it does slightly change how long your pens last. If you remember within 12 hours of your usual injection time, take the dose as soon as you remember. If more than 12 hours have passed, skip it entirely and inject your normal dose the next day. Never double up to compensate for a missed injection. Each skipped dose means a tiny bit of extra medication stays in your pen, stretching it by a day.
Planning Your Refills
At maintenance, three pens run out in just 18 days. If your pharmacy or insurance allows only monthly fills, you’ll need five pens per box to cover a full 30 days. Some insurance plans require prior authorization for Saxenda, and pharmacy delays can take several days. Start the refill process at least a week before you expect to run out, especially if this is a newer prescription where insurance approvals may still be processing.
If cost is a factor, keep in mind that the lower doses during the escalation period use medication more slowly. Some people spread their three pens across the early weeks and then reorder the full five-pen box once they reach maintenance. Knowing exactly how much medication you’ll need at each stage helps you avoid both waste and gaps in treatment.