Site Updates

Treatment Selectors – revised and expanded

Rilpivirine, emtricitabine, tenofovir-DF single tablet regimen added to website

The single tablet regimen of rilpivirine, emtricitabine and tenofovir-DF (Eviplera®, Complera®) has been added to the list of antiretroviral drugs.

Instead of having to select the three components individually and seeing three sets of interactions, this latest update means that interactions are now combined into a single entry.

New comedications for cancer therapy and prevention of bone loss

Three new comedications have been added to the interaction checker. Abiraterone and avelumab are listed in the “cancer therapies” class, and calcitonin (for the prevention of bone loss) is listed in the “other” class.

New herbal preparations

Six new herbal preparations have been added to the interaction checker.

• Ashwagandha (Withania somnifera)
• Ayahuasca
• Black cohosh (Actaea racemose, Cimicifuga racemosa)
• Ginseng (Panax ginseng, Panax quinquefolius)
• Green tea extracts (Camellia sinensis)
• Mucuna pruriens

Please remember that the...

A new antifungal and two new Alzheimer’s drugs

Three new comedications have been added to the interaction checker. Isavuconazole (administered as its water-soluble prodrug isavuconazonium sulfate) is listed in the antifungal class. Donepezil and memantine (for the treatment of Alzheimer’s disease) are listed in the “other” class.

Review of contraceptives and hormone replacement therapy

We have completed a review of the drugs listed in the contraceptive/HRT class of the checker to ensure that the information provided is consistent, clinically useful and up to date.

As a result of this review, HRT summaries were revised to include mention of the estrogen component (to be consistent with combined oral contraceptives) and, where required, interactions were recoded from gre...

Three new comedications

Three new comedications have been added to the interaction checker in recent weeks. Details of the drugs and the classes in which they can be found are shown below.

• Letermovir (Antivirals)
• Semaglutide (Anti-diabetics)
• Silodosin (Overactive bladder agents)

Interactions with Dapivirine

Drug interaction information now available in Spanish

We are pleased to announce that our HIV drug interaction checker is now available in Spanish.

Changes and additions to our Prescribing Resources

We have made some changes to the sections on our Prescribing Resources page to try to make it easier to see what resources are available. PDF files that were previously in the section “Treatment Selectors (by patient characteristics)” have been moved to one of three new sections – “Interactions Explained”, “Key Notes on …”, and “Prescribing and Dosing Guidance”.

In addition, three...

New drugs for the interaction checker

An additional HIV drug and four new comedications have been added to the interaction checker.

New HIV Drug
Enfuvirtide (Fuzeon™, ENF, T20) has been added as an HIV drug in the Entry and Attachment Inhibitors class. Enfuvirtide is a fusion inhibitor and is administered by subcutaneous injection. It has previously been listed on the checker, but only as a comedica...

Two new comedications

New comedications for the interaction checker

Four new comedications have been added to the interaction checker - bulevirtide in the antiviral class, terbutaline in the bronchodilator class, and azilsartan and triamterene in the hypertension/heart failure class. 

Some changes to the drug list

Two new comedications have been added to drug list – alirocumab (Praluent®) in the lipid lowering class and desvenlafaxine (Pristiq®) in the antidepressant class.

We have also decided to remove saquinavir from the list of HIV drugs given its very low usage worldwide.

Dose dependent enzyme induction

A new Prescribing Resource has been added to the website which describes dose dependent enzyme induction and the clinical implications of this. Details are given for the potential dose dependent induction of six drugs - rifampicin, St John's wort, dexamethasone, phenytoin, carbamazepine, and oxcarbazepine.

Effect of gastric surgery on ARV absorption - a new Prescribing Resource

A new Prescribing Resource has been added to the website which details the effect different types of gastric surgery can have on the absorption of antiretrovirals. Three different types of surgery are considered – bariatric surgery, small bowel resection, colonic resection – and their known and expected effects on ARV pharmacokinetics are described.

Additions and Revisions

We have added some new comedications to the interaction checker and revised a few existing interactions.

Four new comedications have been added – zolmitriptan (Anti-migraine), brentuximab vedotin (Cancer therapies), enzalutamide (Cancer therapies) and polatuzumab vedotin (Cancer therapies). Cabergoline h...

Review of interactions between ARVs and HIV single tablet regimens.

We have completed a review of the interactions between ARVs and the single tablet regimens (STRs) used to treat HIV. Many (but not all) of the product labels for the STRs state that the STR should not be coadministered with other ARVs and for this reason such interactions were coded as red on the interaction checker. We have now reassessed all the interactions as, in specific clinical situations...

Some new comedications

Six new comedication have been added to the interaction checker. The drugs and their classes are:

• Alogliptin (Anti diabetics)
• Atomoxetine (Other)
• Brimonidine (Other))
• Colestyramine [cholestyramine] (Other)
• Dexlansoprazole (Gastrointestinal agents)
• Hydroxychloroqine (Antiprotozoals)

The new drugs are available on the website and the...

New drugs added to the interaction checker

A new HIV drug and three new comedications have been added to the interaction checker.

Fostemsavir (Rukobia®), an HIV attachment inhibitor, was recently approved by the FDA for the treatment of HIV-1 infection in heavily treatment-experienced adults with multidrug-resistant HIV-1 infection failing their current antiretroviral regimen due to resistance, intolerance, or sa...

Cabotegravir (oral) and cabotegravir/rilpivirine (long acting)

Two new HIV drugs have been added to the interaction checker. Cabotegravir (oral tablets; Vocabria®) and cabotegravir/rilpivirine (extended-release injectable suspensions; Cabenuva®) have been approved for use in Canada.

For the time being, only summaries of the interactions are available. We will add full references when American and/or European product labels are available (in line wit...

New Prescribing Resource – interactions with integrase inhibitors and cations

Integrase inhibitors can bind to polyvalent cations resulting in potentially clinically significant drug interactions with coadministered cation-containing antacids and other supplements/multivitamins. Management of such interactions often requires the temporal separation of the integrase inhibitor from the cation-containing product.

We have produced a new Prescribing Resource which give...

New names and new comedications

We have renamed some of the comedications in the “Herbal/Supplements/Vitamins” class to make it clearer if possible interactions are due to the presence of multivitamins or to the comedication itself. Existing interactions have been revised to refer to when the comedication is given in a multivitamin preparation and new interactions have been added for when the comedication is given alone. The f...

Albuvirtide – a new ARV added to the interaction checker

Albuvirtide (Aikening®) has been added to the interaction checker on the website and is available via an update on the iChart app.

Albuvirtide is a long acting fusion inhibitor and has marketing approval in China for the treatment of HIV. Albuvirtide is administered once weekly by intravenous infusion.

A couple of new comedications

New comedications and a few changes to existing names

Six new comedications have been added to the interaction checker:

• Benazepril (Hypertension and Heart Failure Agents)
• Etidocaine (Anaesthetics and Muscle Relaxants)
• Minaxolone (Anaesthetics and Muscle Relaxants)
• Piperacillin (Antibacterial)
• Tinidazole (Antibacterials)

Updates to dolutegravir and some enzyme/transporter inducers

Some changes have been made to interactions with dolutegravir (Tivicay), dolutegravir/abacavir/lamivudine (Triumeq) and dolutegravir/lamivudine (Dovato) with the known enzyme/transporter inducers, rifampicin, rifapentine, carbamazepine, oxcarbazepine, eslicarbazepine, phenytoin, phenobarbitone, primidone and St John’s Wort. Summaries for these interactions have been revised and in some cases the...

New ARV coformulations added – Dovato® and Triumeq®

Two dolutegravir-containing coformulations have been added to the interaction checker - Dovato® (dolutegravir and lamivudine) and Triumeq® (dolutegravir, abacavir and lamivudine).

New and updated treatment selectors

Three new comedications

Three new comedications have been added to the interaction checker. Ciclesonide and flunisolone are listed in the steroid class and have a lower potential to cause corticosteroid-related systemic effects compared to some other inhaled corticosteroids. Red yeast rice is a herbal preparation and contains monacolin K, a natural component with ...

A few new comedications

Four new comedications have been added to the interaction checker and takes the total number of comedications on the website to ~730.

Additional comedications

Nine new comedications have been added to the interaction checker in response to requests received during the last 12 months or so. This takes the total number of interactions on the website to over 26,000.

Updated chart for hormone therapy for gender transitioning

Updated treatment selectors

Look for alternatives – a new feature for the interaction checker

A new feature has been added to the website interaction checker to make it easier to find possible alternatives when an interaction is amber or red. For these interactions, you now have the option to click on “look for alternatives”. This will take you to a new page showing interactions for the antiretroviral with other comedications in the same class.

The look for alternatives option is...

New Comedications

Six new comedications have been added to the interaction checker, taking the total number of comedications to nearly 720. The new comedications and their therapeutic classes are shown below:

• Acamproasate (Other)
• Adalimumab (Immunosuppressants)
• Cannabidiol (Other)
• Cetuximab (Cancer Therapies)
• Evolocumab (Lipid Lowering Agents)
• Vortioxetine (Antid...

Expanded atazanavir listing

Following on from providing two listings for darunavir according to whether it is used with cobicistat or ritonavir, we have now split atazanavir into three options.

Like darunavir, atazanavir can be used with either cobicistat or ritonavir, but in addition it is licensed in some geographical regions for use without a pharmacokinetic enhancer in certain patients.

Atazanavir now a...

New Antiretroviral Combinations

Over the last few months we have been updating the list of antiretrovirals to include specific combinations and new coformulations.

• Darunavir has been split into darunavir/cobicistat (coformulated as Prezcobix or Rezolsta) and darunavir + ritonavir (available as Prezista + Norvir). The new single tablet regimen of darunavir/cobicistat/emtricitabine/tenofovir alafenamide (Symtuza) ha...

New HIV Drugs - Pifeltro® and Delstrigo®

Two new HIV medications have been added to the interaction checker. Doravirine is a non-nucleoside reverse transcriptase inhibitor (NNRTI) and was approved by the FDA in August 2018 for the treatment of HIV-1 in combination with other antiretrovirals in adult patients with no prior antiretroviral treatment experience.

Doravirine is available as a single agent (Pifeltro®) and as a once-da...

Ibalizumab (Trogarzo®)

Interactions with ibalizumab have been added to the website and HIV iChart app. 

Ibalizumab is a monoclonal antibody which blocks HIV-1 from infecting CD4 cells by binding to domain 2 of CD4 and interfering with post-attachment steps required for viral entry. It is given by intravenous infusion every two weeks and must be used in combination with other antiretroviral drugs. No ...

Bictegravir/Emtricitabine/Tenofovir alafenamide

Interactions with bictegravir/emtricitabine/tenofovir alafenamide are now included on the website, HIV i Chart app and printable charts. For ease of viewing on small screens, the listing appears as “Bictegravir/FTC/TAF”.

Bictegravir/emtricitabine/tenofovir alafenamide (Bictarvy®) is a fixed dose combination and is indicated as a complete regimen for the treatment of HIV-1 infection....

Updated printable materials

Yellow interactions - all comedications reassessed

Yellow interactions – a progress report

A further batch of comedications have been reassessed using the new interaction classification system (which includes “yellow”). This takes the total number of therapeutic drug classes updated to 26, and leaves just 13 classes still to update. The latest therapeutic classes to be updated are.

• Anaesthetics and muscle relaxants
• Analgesics
• Anthelmintics
• Antia...

Yellow interactions - first classes of comedications have been reassessed

Updates to Contraceptives and HRT

Comedications within the Contraceptive and HRT class have been revised and the listing expanded to include various routes of administration and indications. The new listing now includes different hormonal contraceptive methods such as combined oral contraceptives (COC), progestogen only pills (POP), implants, vaginal rings, intra-uterine devices (IUD), patches and depot injections.

All i...

Yellow - a new addition to the interaction classification system

Over the next few months we will be expanding our interaction classification system to include a new “yellow” interaction, which will sit between the original green and amber classifications. Yellow interactions are likely to be of weak intensity and as such, additional action or monitoring, or a dosage adjustment is unlikely to be required. However, healthcare professionals should be aware of t...

New preparations added to Hormone Therapy for Gender Transitioning.

Our guide to interactions with Hormone Therapy for gender transitioning has been updated to include triptorelin, testosterone enanthate or cypionate, and mixed testosterone esters. A new comment about the thromboembolic risk with conjugated estrogens has been added, as well as new review article in the reference section.

The update guided is found in the Interaction Cha...

New comedications and new interaction charts

The following drugs have been added to the comedication list, taking the number of comedications to over 650 drugs.

• Hypertension/Heart Failure Agents – Terazosin, Sacubitril
• Herbals - African Potato, Cat’s claw, Goldenseal root
• Other - Cyproterone acetate, Goserelin, Leup...

Interactions with RPV/FTC/TAF (Odefsey)

All versions (web, app, printable) of the interaction charts have been updated to include Odefsey®, a fixed-dose combination tablet containing rilpivirine, emtricitabine (FTC) and tenofovir alafenamide (TAF). 

Interactions are listed under the abbreviation rilpivirine/FTC/TAF and, for the printable charts, the combination has been included as a NNRTI.

Additional Herbal Preparations

Nine new herbal preparations have been added to the comedication list. Note, for many of these preparations, pharmacokinetic studies have not been performed and the clinical effect has been estimated based on in vitro findings. In addition, it is unclear whether in vitro results with extracts from one part of the plant (e.g. leaf) are representative of other parts of the plants (e.g. root, bark)...

Interactions with FTC/TAF (Descovy)

The web and app versions of the interaction charts have been updated to include Descovy®, a fixed-dose combination tablet containing emtricitabine (FTC) and tenofovir alafenamide (TAF). Interactions are listed under the abbreviation emtricitabine/TAF and the combination is classified as a nucleoside/tide analogue.

We are preparing updated printable charts to ...

Les tables d’interactions médicamenteuses sont disponibles en français

Anticoagulants and Antiplatelets

Four new comedications have been added to the Anticoagulants, Antiplatelets and Fibrinolytic class. The new drugs are apixaban, dipyridamole, edoxaban and fondaparinux. All versions of the interaction charts (web, app and printable) have been updated with these new additions.

In related news, a new treatment selector for the class of Anticoagulants and Antiplatelets has been pr...

Elbasvir/grazoprevir - a new addition to the comedication list

Updates to elvitegravir/cobicistat interactions

Interactions with E/C/F/TAF (Genvoya)

A few new comedications

Expansion of the comedications list to over 600 drugs

Corticosteroids – new comedications and treatment selector

Updated Printable Charts

Expanded and Revised Listings for Contraceptives/HRT and Illicit/Recreational Comedications

Interactions with Cobicistat

Cobicistat (Tybost®) as a single agent is licensed for the pharmacokinetic enhancement of atazanavir or darunavir. Interactions with cobicistat and comedications have now been added to web and app versions of the charts and, for ease of use, cobicistat can be found listed as protease inhibitor alongside atazanavir and darunavir. The printable versions of the charts will be updated shortly.

Empty Green Project

New Comedications

• Bedaquiline (Antibacterial)
• Macitentan (Hypertension / Heart Failure Agents)
• Simeprevir (Antivirals)
• Sofosbuvir (Antivirals)

Updated charts to include dolutegravir's European product label

Interactions with Dolutegravir

New cytotoxics added as comedications

Interactions with Elvitegravir/Cobicistat

Elvitegravir, an integrase inhibitor, was licensed in America during 2012 and is now licensed for use in Europe. Interactions with elvitegravir/cobicistat have been added to the website charts and the HIV iChart app - the printable charts will be updated in the next week. Elvitegravir is available only as a fixed dosed combination tablet (Stribild®) with cobicistat, emtricitabine and tenofovir. ...

Printable Charts Updated

New drugs added to the interaction charts

ARVs for patients with swallowing difficulties (updated January 2013)

Updated Printable Charts

WHO Essential Medicines

Empty Amber Project

ARVs for patients with swallowing difficulties.

We have produced a list of ARV formulations that can be used for patients who have difficulty swallowing.  Further details (and a link to the document) can be found in the Interaction Charts / Treatment Selector section of this website.

Expanded General Anaesthetics Section

Rilpivirine

Trade Names

Boceprevir & Telaprevir and Updated Printable Charts.

New Format Fact Sheets.

The pharmacokinetic fact sheets are now available in pdf format.  As well as showing the structure and trade names for each drug, the fact sheets summarise key Information on pharmacokinetic parameters, metabolism and distribution.  Fact sheets are currently available for the PIs, NRTIs, NNRTIs, entry/integrase inhibitors and hepatitis antivirals.

Theoretical interactions for NRTIs, maraviroc and raltegravir.

New anticoagulants added.

Two new anticoagulants have been added to the interaction charts - dabigatran (a direct thrombin inhibitor) and rivaroxaban (a direct Factor Xa inhibitor).

The online charts and iPhone and Android apps have been updated to include these new drugs.  The printable version of the charts will be updated in the next few months.

Printable Charts

Changes and additions to the drug interaction charts

There have been a few minor changes to the comedication classes on the charts and over 30 new drugs have been added.  HIV-Charts2Go have been updated with these changes and the printable charts will be updated over the next few weeks.

Calcium channel antagonists are now named calcium channel blockers; hypertension drugs are included with heart failure agents and the class renamed ...

Changes to website

Website Maintenance

The website is having to undergo essential maintenance on its infrastructure which will be completed by August. During this time user access to the site will not be affected, but it will mean that we are unable to update charts and other parts of the site. However, the latest news will continue to be added and email updates will be sent once a month.

Extensive updates to charts

The interaction database has been extensively updated to reflect changes in the European Summaries of Product Characteristics and US Prescribing Information. The printed version and PDA version of the charts have now been updated with all the web changes.

New drugs added to the charts

One of our projects for this year is to increase the number of WHO Essential Medicines listed on the charts. We have recently added a batch of new drugs which include some of these drugs, as well as other drugs added in response to queries we have received. The drugs listed below have been added to the web charts and the PDA charts (HIV-Charts2Go). Where possible, they will be added to the print...

New format interaction charts

The format of the interaction charts has been changed to make searching for interactions easier and to distinguish between those interactions for which data exists (“referenced interactions”) and those which are predicted based on routes of metabolism and elimination (“theoretical interactions”).

The search interface has been simplified so that there in now only one option. Previously ...

New fact sheets available

New fact sheets have been added to the Pharmacology Resources section of the website. These fact sheets contain information on the chemical nature and structure of a drug, its key pharmacokinetic parameters and its metabolism and distribution.

Facts sheets on elvitegravir and beviramat have been added to the Entry/Integrase/Maturation Inhibitors section.

A new section on Hep...

New drugs added to interaction charts

There are several additions to the interactions charts – both new drugs and a new class.

As well as introducing new drugs to existing classes, we have introduced a new class of drugs – Heart Failure Agents – which includes ACE inhibitors, angiotensin II receptor antagonists and diuretics. We have also expanded the steroid section to include not just the oral contraceptive steroids; no...

Interaction Charts reviewed and updated.

Many changes and additions have been made to the interactive interactions charts as a result of updates to SPCs and Prescribing Information. New versions of the printed charts and HIV-Charts2Go are available with these changes and additions.

Personalised, printable reports now available for interaction charts

NEW - personalised, printable reports
We have launched a new feature for the interactive charts that allows you to create and save a summary of your chosen interactions in pdf format. Just make your drug selection in the usual way and, when the table of interactions is displayed, you will see a new option to generate a personalised report (please note that this feature is limited to ...

New Interactive Charts and Updated Printable Charts

New Interactive Charts for Entry and Integrase Inhibitors
Interactive charts for Maraviroc and Raltegravir are now available. These charts are less extensive than the PI and NNRTI charts and have been compiled from the Summary of Product Characteristics, Prescribing Information, meeting abstracts and full papers. With a few exceptions, only drugs cited in these sources are listed. If...

New Drugs for the Interaction Charts

There have been some changes and additions to the Interaction Charts over the last few weeks.

On the Protease Inhibitor chart, amprenavir has been replaced by fosamprenavir. The interactions are essentially the same, apart from a few amber interactions that were due to the alcohol content of amprenavir oral solution and are not relevant for fosamprenavir.

On the NNRTI chart, ...

Varenicline Added to Charts

The smoking cessation drug varenicline (Champix®, Chantix®) has been added as a row to the interactive charts and will be included on the printed charts when they are next updated.

Drug interactions are not expected with varenicline as it has been shown in vitro not to inhibit or induce cytochrome P450 enzymes. Since less than 10% of varenicline is metabolised, CYP P450 inhibitors or ...

Additional information on hormonal contraceptives.

Information on hormonal contraceptives is listed on the charts in the steroid section under ethinylestradiol and progesterone/progestogens. The information available is predominantly for daily oral contraceptives, but other routes and frequencies of administration are now available.

We have produced a chart which details the various forms of hormonal contraception and, for the newer form...

Updates to Interaction Charts

The following drugs have been added as rows to the interaction charts:
Etravirine – new NNRTI
Maraviroc – new entry inhibitor
Elvitegravir – new integrase inhibitor
Raltegravir – new integrase inhibitor

A summary and description have been provided for those interactions where studies have been performed. If no studies have been performed, we have indicated a theor...

Maraviroc Interactions

Interactions with maraviroc are now available on the website. Interactions with other HIV drugs have been added as new row to the existing charts.

Etravirine Interactions.

Interactions with etravirine are now available on the website.

Etravirine (TMC125) is a next generation NNRTI that shows high intrinsic activity against both wild-type HIV-1 and strains with resistance-inducing mutations. Etravirine is metabolised by CYP3A4, CYP2C19 and UDP-glucuronyl transferase, and has been shown to induce CYP3A and inhibit CYP2C19 in vivo.

A substantial i...

Drug Interaction Summaries

Drug interaction summaries have now been added for all interactions where further information is available.

This new feature summarises key data from SPCs, Prescribing Information and published studies. Details of the direction and magnitude of the interaction and any management recommendations are given. These summaries will form the basis of the new PDA version of the charts which ...

Updates to PI charts - darunavir added

Darunavir (Prezista, TMC114) has now been added to the interaction charts in full. Currently only interactions detailed in the Summary of Product Characteristics or Prescribing Information are referenced. Details of interactions presented at meetings will be added in the next few months.

The other PIs have been updated also to reflect changes in made in the wording or data presente...

Updates to NNRTI Charts

The NNRTI charts have been updated to reflect changes made in the wording or data presented in the most recent versions of the European Summaries of Product Characteristics and the US Prescribing Information.

New or amended interaction data have been added as follows:
Delavirdine Prescribing Information, updated from 2001 to February 2006 (carbamazepine, didanosine,...

NRTI Charts Now Available

Interaction charts with nucleoside and nucleotide analogues have now been completed and are available in interactive and printable formats. The NRTI charts feature a summary of the interaction as well as a full description (we are currently adding summaries to the PI and NNRTI charts).

The NRTI charts have been compiled from the Summaries of Product Characteristics, Prescribing Inform...

Interaction Charts

Interaction Charts - antimalarial drugs revised and expanded.

Tipranavir now available on the Interaction Charts

Tipranavir (Aptivus), a non-peptidic protease inhibitor, was recently licensed in Europe (FDA approval was granted earlier this summer). We have now completed our evaluation of the literature and have added tipranavir interactions to the Interaction Charts.

Please note that as tipranavir (a powerful CYP3A and P-gp inducer) is coadministered with ritonavir (a potent inhibitor), predict...

Presentation - Medscape Webcast. Optimizing Antiretroviral Therapy for HIV: Key Pharmacologic Concerns

Presentations from the 7th HIV Pharmacology Workshop

The 7th International Workshop on Clinical Pharmacology of HIV Therapy was held this year in Lisbon. Several members of LHPG attended and presented data. Oral presentations were given by Laura Dickinson, Sara Gibbons and Saye Khoo, and poster presentations were given by Laura Else and Wai San Kwan. 

Full details of all presentations from this meeting, will be available on www.hi...

Interaction Charts - antimalarial drugs revised and expanded.

The Drug Interaction Charts have been revised to include extra antimalarial drugs and additional information on existing drugs.

The following antimalarial drugs have been added to the interaction charts:
- Amodiaquine
- Artemesinins (Artemether, Artesunate)
- Primaquine
- Quinine
- Sulfadoxine/Pyrimethamine

Further details on the nature of interactions with at...

Poster Presentations from 13th CROI Meeting.

Presentations from the recent meeting in Denver by members of the Liverpool HIV Pharmacology Group have now been added to the About Us section of this website. The posters are available as Acrobat pdf files and contain a link to the abstract from the Conference website.

Dr Andrew Owen presented the results of a proof of concept study to assess the impact of the G516T polymorphism on C...

Dynamic Interaction Charts

The latest site update is a substantial redevelopment of the Interaction Charts. The new chart interface provides you with a greater level of flexibility, allowing you to select the specific interactions you need to review. This dynamically driven process offers detailed information on the predicted interactions of specified multiple drug combinations, and where appropriate, recommendations for ...