How to Avoid or Fix a Comma Splice

Commas, commas, commas. There are so many rules, so many opinions, and so many ways to use this tiny punctuation mark. I previously waded into comma usage with commas and conjunctions, and now I’ll swim further into the comma pool with comma splices.

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A “splice” is a joint or joining of two things. To me, splicing sounds a bit…painful? And that negative connotation is appropriate here—we don’t want to use comma splices. So what is this splice joining together? Two complete sentences. And what’s the big deal? Well, this isn’t a comma’s job!

Students love their program’s PA Qbank, the teaching images are their favorite part.

This example has two complete sentences (ones that have their own noun and verb): (1) Students love their program’s PA Qbank (cool). (2) The teaching images are their favorite part (I don’t blame them). Since these sentences can stand on their own, separating them with a period would be one way to fix the splice. 

Students love their program’s PA Qbank. The teaching images are their favorite part.

And what did we learn from the commas and conjunctions blog? A conjunction can be used after a comma to join two complete sentences.

Students love their program’s PA Qbank, and the teaching images are their favorite part.

But wait—we could also use a semicolon here!

Students love their program’s PA Qbank; the teaching images are their favorite part.

There are so many ways to fix a comma splice. How would you alter this sentence?

The patient is started on prednisone, what other medication is indicated for the treatment of this complication of systemic lupus erythematosus?

I would make the comma a period instead. [Note “this complication” refers to something that was mentioned before these sentences.]

The patient is started on prednisone. What other medication is indicated for the treatment of this complication of systemic lupus erythematosus?

How about this one?

Lispro and aspart are two common rapid-acting insulins, the duration of action for these medications is approximately two to four hours.

I would choose either a period or a semicolon instead of the comma, or I would rewrite the sentence.

Lispro and aspart are two common rapid-acting insulins and have an approximately two- to four-hour duration of action.

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That wasn’t too bad, was it? When I jot things down or write early first drafts, I use comma splices all the time. Just remember to keep an eye out for them and either rewrite your sentence or change that comma to a period or semicolon.