Why Isn't Cialis Recommended To Be Split?

In our latest question and answer, the pharmacist discusses why Cialis tablets are not recommended to be split.

Question

Why is it recommended to not split tablets of tadalafil? I have been splitting the 20 mg tablets and taking them daily for over a year, for ED. what are the problems that could arise if you take split tablets over an extended period of time?

Asked by Scott On Apr 14, 2019

Answered by
Medical Content Reviewed By PharmacistAnswers Staff

On Apr 17, 2019
Tablet Splitter With Tablet In It With Text- Splitting Cialis Tablets

Overview

You are correct that the manufacturer of Cialis (tadalafil) recommends not to cut or split the tablets. Per the prescribing information:[1]

"Do not split CIALIS tablets; entire dose should be taken."

There are a few reasons why the manufacturer recommends taking Cialis tablets intact, but overall, the potential consequence of splitting tablets is likely, not significant.

In fact, it is not uncommon for prescribers to recommend to split Cialis tablets as a potential cost-saving measure for patients.[2]


Why Shouldn't Cialis Be Split?

There are two main reasons why Cialis (and associated generic) tablets are not recommended to be cut or split:

  • Brand name Cialis tablets have a non-symmetrical shape.
  • Generic Cialis tablets (tadalafil), many of which are symmetrical, are film-coated. Splitting these tablets will destroy the film-coating.

Aside from the two reasons above, other reasons exist for the recommendation not to split the tablets. They include:

  • Split Cialis tablets have not been tested for safety or efficacy.
  • Neither the brand nor the generic tablets are scored.

Cialis Shape

Brand name Cialis tablets, like Viagra, have an odd, non-symmetrical shape. Below is an image of the 20 mg Cialis tablet:

Cialis Tablets Shape

The non-symmetrical shape of Cialis tablets would make it difficult to evenly split into two pieces. This may lead to inconsistent dosing.

Generic Cialis products (tadalafil) are recommended not to be split too, even though most of them have a symmetrical shape. The recommendation not to split these is likely mostly due to the film-coating.

It is important to point out that neither the brand nor the generic tablets are scored. Even with the use of a pill splitter, non-scored tablets can be difficult to split evenly.[3]


Lack Of Data

During clinical trials for Cialis, the manufacturer (Eli Lilly) only looked at the use of whole tablets. There is no safety or efficacy data on the use of split tablets. Therefore, the generic products have no data on split tablets either.[4]


Film-Coating

Generic tadalafil tablets are film-coated. Splitting the tablets destroys the film coating.

There are a variety of reasons why a drug tablet may be film coated. Film-coated tablets are often easier to swallow and less likely to cause throat irritation than non-coated tablets.[5]

Additionally, some film-coatings are designed to protect the tablet from dissolving in the stomach. This can not only reduce the potential of certain side effects (e.g. nausea), it can also help to make the drug more effective by preventing early degradation by stomach acid.[6]

According to the prescribing information for both Cialis and generic tadalafil products, the film coating is not a delayed-release mechanism and is therefore likely intended only to ease in swallowing and to protect the tablets from excess moisture.[7]


Can You Split Them?

Having said all of the above, splitting/cutting erectile dysfunction (ED) drugs like Cialis is a fairly common practice. Your doctor may even recommend you do it if you need to adjust your dose or as a cost-saving measure.

There have been no reported safety issues cutting Cialis (or generic tadalafil) tablets, and they are not listed on the ISMP list of medications that shouldn't be crushed.[8]

If you have the brand name tablets, and your doctor has recommended splitting them to adjust your dose or as a cost-saving measure, take care in doing so since it can be difficult to cut the oddly shaped tablets (and they aren't scored).

If you have a generic tadalafil tablet, most are symmetrical and should be easier to split evenly than the brand name ones. However, be aware that they may be slightly more difficult to swallow since the film-coating will no longer be intact. They may also have an unpalatable taste.


Summary

Brand Cialis (as well as generic tadalafil) tablets are not recommended to be split for a variety of reasons (e.g. they have a film-coating). Nevertheless, splitting them is a common practice which generally shouldn't have significant negative consequences.

References
  1. ^ Cialis Prescribing Information. AccessFDA
  2. ^ Which drug for erectile dysfunction? Havard Health
  3. ^ Accuracy of tablet splitting: Comparison study between hand splitting and tablet cutter. PubMed
  4. ^ Dispensing Drugs for Erectile Dysfunction. Pharmacist's Letter (Subscription Required)
  5. ^ Development of an easily swallowed film formulation. PubMed
  6. ^ Using medication: Oral medications. PubMed
  7. ^ Tadalafil Monograph DAILYMED
  8. ^ Oral Dosage Forms That Should Not Be Crushed ISMP

About the Pharmacist

Dr. Brian Staiger Pharm.D

Dr. Brian Staiger is a licensed pharmacist in New York State and the founder of PharmacistAnswers.com. He graduated from the University At Buffalo with a Doctor of Pharmacy degree in 2010. He has been featured in numerous publications including the Huffington Post as well as a variety of health and pharmacy-related blogs. Please feel free to reach out to him directly if you have any inquiries or want to connect! He's answered thousands of medication and pharmacy-related questions and he's ready to answer yours! Brian.Staiger@PharmacistAnswers.com Office: 716-389-3076

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