That’s right! None of the listed antiretroviral therapies have known interactions with GLP-1 agonists.

GLP-1 agonists are metabolized by endopeptidases and therefore do not result in major drug–drug interactions with most antiretrovirals, including doravirine^{2, 6}.

However, GLP-1 agonists are known to inhibit gastric acid secretion, which warrants caution and close monitoring when combined with atazanavir and oral rilpivirine, two antiretrovirals which require low gastric pH for optimal absorption.⁶

References:
1. Biktarvy SmPC; 2. Delstrigo SmPC; 3. Dovato SmPC; 4. Atripla SmPC; 5. Rezolsta SmPC; 6. Zino L, Tack CJ, Richel O, Burger DM. HIV Med. 2023;24(10):1029-1034. doi:10.1111/hiv.13521

That’s not correct. None of the listed antiretroviral therapies have known interactions with GLP-1 agonists.

GLP-1 agonists are metabolized by endopeptidases and therefore do not result in major drug–drug interactions with most antiretrovirals, including doravirine^{2, 6}.

However, GLP-1 agonists are known to inhibit gastric acid secretion, which warrants caution and close monitoring when combined with atazanavir and oral rilpivirine, two antiretrovirals which require low gastric pH for optimal absorption⁶.

References:
1. Biktarvy SmPC; 2. Delstrigo SmPC; 3. Dovato SmPC; 4. Atripla SmPC; 5. Rezolsta SmPC; 6. Zino L, Tack CJ, Richel O, Burger DM. HIV Med. 2023;24(10):1029-1034. doi:10.1111/hiv.13521

That’s right! Dovato® interacts with magnesium‑ and aluminium‑containing antacids such as Gaviscon®.

Dolutegravir (in Dovato®) can bind with the calcium and magnesium ions present in antacids such as Gaviscon®⁶, forming complexes that reduce absorption and lower drug levels. As a result, this interaction could be managed by co-administration with food or spacing the antacid at least 6 hours before or 2 hours after the daily dose of Dovato®

The INSTI-free regimens listed (including Delstrigo®) can be co‑administered with antacids without timing or food adjustments.^1-3,5

References:
1. Symtuza SmPC; 2. Delstrigo SmPC; 3. Rezolsta SmPC; 4. Dovato SmPC; 5. Atripla SmPC; 6. Gaviscon Double Action Aniseed Oral suspension SmPC

That’s not correct. Of the antiretroviral regimens listed, only Dovato® is affected by magnesium or aluminium containing antacids such as Gaviscon®.

Dolutegravir (in Dovato®) can bind with the calcium and magnesium ions present in antacids such as Gaviscon®⁶, forming complexes that reduce absorption and lower drug levels. As a result, this interaction could be managed by co-administration with food or spacing the antacid at least 6 hours before or 2 hours after the daily dose of Dovato®

The INSTI-free regimens listed (including Delstrigo®) can be co‑administered with antacids without timing or food adjustments.^1-3,5

References:
1. Symtuza SmPC; 2. Delstrigo SmPC; 3. Rezolsta SmPC; 4. Dovato SmPC; 5. Atripla SmPC; 6. Gaviscon Double Action Aniseed Oral suspension SmPC

That’s right! Carbamazepine is the only option listed that is contraindicated with Delstrigo®.

Carbamazepine is a CYP3A4 inducer which significantly decreases doravirine plasma concentration. All the other anti‑epileptics listed — including clonazepam, sodium valproate, lamotrigine, levetiracetam, and lacosamide — are not enzyme inducers and do not reduce doravirine exposure.

References:
1. Delstrigo SmPC

That’s not quite right. Of the options listed, only carbamazepine is contraindicated with Delstrigo®.

Carbamazepine is a CYP3A4 inducer which significantly decreases doravirine plasma concentration. All the other anti‑epileptics listed — including clonazepam, sodium valproate, lamotrigine, levetiracetam, and lacosamide — are not enzyme inducers and do not reduce doravirine exposure.

References:
1. Delstrigo SmPC

That’s right! Biktarvy® interacts with the polyvalent cations often contained in protein shakes.

Protein shakes often contain polyvalent cations such as calcium, iron and magnesium⁶. Bictegravir (in Biktarvy®) can chelate with polyvalent cations, forming complexes that reduce absorption and lower drug levels⁴.

INSTI free regimens listed (including Delstrigo®) do not have significant chelation interactions and can be co‑administered with protein shakes without timing or food adjustments¹.

References:
1. Delstrigo SmPC; 2. Odefsey SmPC; 3. Rezolsta SmPC; 4. Biktarvy SmPC; 5. Atripla SmPC; 6. González-Weller D, et al. Foods. 2023 Jun 1;12(11):2238. doi: 10.3390/foods12112238.

That’s not correct. Biktarvy® interacts with the polyvalent cations often contained in protein shakes.

Protein shakes often contain polyvalent cations such as calcium, iron and magnesium⁶. Bictegravir (in Biktarvy®) can chelate with polyvalent cations, forming complexes that reduce absorption and lower drug levels⁴.

INSTI free regimens listed (including Delstrigo®) do not have significant chelation interactions and can be co‑administered with protein shakes without timing or food adjustments¹.

References:
1. Delstrigo SmPC; 2. Odefsey SmPC; 3. Rezolsta SmPC; 4. Biktarvy SmPC; 5. Atripla SmPC; 6. González-Weller D, et al. Foods. 2023 Jun 1;12(11):2238. doi: 10.3390/foods12112238.

That’s right! Dolutegravir significantly increases metformin levels.

When co-administered with dolutegravir 50 mg once-daily, metformin exposure is increased by approximately 80%. A dose adjustment of metformin should be considered when starting and stopping coadministration of Dovato® with metformin, to maintain glycaemic control.

In patients with moderate renal impairment a dose adjustment of metformin should be considered when co-administered with Dovato®, because of the increased risk for lactic acidosis in patients with moderate renal impairment due to increased metformin concentration¹

References:
1. Dovato SmPC; 2. Delstrigo SmPC; 3. Biktarvy SmPC; 4. Triumeq SmPC; 5. Atripla SmPC

That’s not correct.

When co-administered with dolutegravir 50 mg once-daily, metformin exposure is increased by approximately 80%. A dose adjustment of metformin should be considered when starting and stopping coadministration of Dovato® with metformin, to maintain glycaemic control.

In patients with moderate renal impairment a dose adjustment of metformin should be considered when co-administered with Dovato®, because of the increased risk for lactic acidosis in patients with moderate renal impairment due to increased metformin concentration¹

References:
1. Dovato SmPC; 2. Delstrigo SmPC; 3. Biktarvy SmPC; 4. Triumeq SmPC; 5. Atripla SmPC

That’s right! Of the options listed, only Biktarvy® is contraindicated with Rifabutin.

Rifabutin is a moderate inducer of CYP3A, UGT1A1, and P‑gp, which can substantially lower bictegravir and tenofovir alafenamide exposure. The Bikatarvy® SmPC advises against coadministration of bictegravir- or TAF‑containing single‑tablet regimens with rifabutin because of the risk of subtherapeutic antiretroviral levels.

What about the other regimens?

• Delstrigo® : Rifabutin induces doravirine metabolism; if co-administered with rifabutin, the doravirine dose should be increased to 100 mg twice daily. This is achieved by adding one 100 mg tablet of doravirine (as a single agent), to be taken approximately 12 hours apart from the dose of Delstrigo®
• Triumeq® or Dovato®: These dolutegravir‑containing regimens are compatible with rifabutin and do not require dolutegravir dose adjustment.
• Atripla®: Efavirenz‑based therapy can be used with rifabutin, however, since efavirenz induces rifabutin metabolism, the daily dose of rifabutin should be increased by 50%. You should consider doubling the rifabutin dose in regimens where rifabutin is given 2 or 3 times a week in combination with Atripla®.

References:
1. Delstrigo SmPC; 2. Biktarvy SmPC; 3. Dovato SmPC; 4. Triumeq SmPC; 5. Atripla SmPC

That’s not correct. Of the options listed, only Biktarvy® is contraindicated with Rifabutin.

Rifabutin is a moderate inducer of CYP3A, UGT1A1, and P‑gp, which can substantially lower bictegravir and tenofovir alafenamide exposure. The Bikatarvy® SmPC advises against coadministration of bictegravir- or TAF‑containing single‑tablet regimens with rifabutin because of the risk of subtherapeutic antiretroviral levels.

What about the other regimens?

• Delstrigo® : Rifabutin induces doravirine metabolism; if co-administered with rifabutin, the doravirine dose should be increased to 100 mg twice daily. This is achieved by adding one 100 mg tablet of doravirine (as a single agent), to be taken approximately 12 hours apart from the dose of Delstrigo®
• Triumeq® or Dovato®: These dolutegravir‑containing regimens are compatible with rifabutin and do not require dolutegravir dose adjustment.
• Atripla®: Efavirenz‑based therapy can be used with rifabutin, however, since efavirenz induces rifabutin metabolism, the daily dose of rifabutin should be increased by 50%. You should consider doubling the rifabutin dose in regimens where rifabutin is given 2 or 3 times a week in combination with Atripla®.

References:
1. Delstrigo SmPC; 2. Biktarvy SmPC; 3. Dovato SmPC; 4. Triumeq SmPC; 5. Atripla SmPC

That’s right! None of the listed common chemsex drugs are known to cause a clinically significant interaction with Delstrigo®.

None of the listed chemsex drugs are known to cause significant pharmacokinetic interactions with Delstrigo®.

References:
1. Delstrigo SmPC; 2. Liverpool HIV Drug Interactions Prescribing Resources – www.hiv-druginteractions.org/prescribing_resources/hiv-summaries-nnrti (Accessed January 2026)

That’s not correct. None of the listed common chemsex drugs are known to cause a clinically significant interaction with Delstrigo®.

None of the listed chemsex drugs are known to cause significant pharmacokinetic interactions with Delstrigo®.

References:
1. Delstrigo SmPC; 2. Liverpool HIV Drug Interactions Prescribing Resources – www.hiv-druginteractions.org/prescribing_resources/hiv-summaries-nnrti (Accessed January 2026)

*please refer to SmPC to see estimated in vivo release rate (mcg/day) at different points in time

That’s right! Efavirenz containing regimens (e.g. Atripla®) may reduce the effects of hormonal contraceptives.

Efavirenz induces CYP3A metabolism which is predicted to significantly decrease levonorgestrel levels, potentially reducing its effects. One 48-week study found that levonorgestrel contraception fails in 15% of women taking efavirenz.  A reliable method of barrier contraception must therefore be used in addition to hormonal contraceptives.

*please refer to SmPC to see estimated in vivo release rate (mcg/day) at different points in time

References:
1. Biktarvy SmPC; 2. Dovato SmPC; 3. Triumeq SmPC; 4. Atripla SmPC; 5. Odefsey SmPC; 6. Delstrigo SmPC; 7. Scarsi K et al. CROI 2015. Oral abstract 85LB.

That’s not correct. Efavirenz containing regimens (e.g. Atripla®) may reduce the effects of hormonal contraceptives.

Efavirenz induces CYP3A metabolism which is predicted to significantly decrease levonorgestrel levels, potentially reducing its effects. One 48-week study found that levonorgestrel contraception fails in 15% of women taking efavirenz.  A reliable method of barrier contraception must therefore be used in addition to hormonal contraceptives.

*please refer to SmPC to see estimated in vivo release rate (mcg/day) at different points in time

References:
1. Biktarvy SmPC; 2. Dovato SmPC; 3. Triumeq SmPC; 4. Atripla SmPC; 5. Odefsey SmPC; 6. Delstrigo SmPC; 7. Scarsi K et al. CROI 2015. Oral abstract 85LB.

That’s right! Cobicistat can increase the risk of adrenal suppression and Cushing’s when taken with a corticosteroid.

Symbicort contains budesonide, an inhaled corticosteroid. Budesonide is metabolized by CYP3A4. Cobicistat is a strong CYP3A inhibitor and can markedly increase systemic exposure to inhaled corticosteroids like budesonide, raising the risk of adrenal suppression and Cushing’s syndrome

References:
1. Biktarvy SmPC; 2. Delstrigo SmPC; 3. Dovato SmPC; 4. Triumeq SmPC; 5. Atripla SmPC; 6.  Symtuza SmPC

That’s not correct. Cobicistat can increase the risk of adrenal suppression and Cushing’s when taken with a corticosteroid.

Symbicort contains budesonide, an inhaled corticosteroid. Budesonide is metabolized by CYP3A4. Cobicistat is a strong CYP3A inhibitor and can markedly increase systemic exposure to inhaled corticosteroids like budesonide, raising the risk of adrenal suppression and Cushing’s syndrome

References:
1. Biktarvy SmPC; 2. Delstrigo SmPC; 3. Dovato SmPC; 4. Triumeq SmPC; 5. Atripla SmPC; 6.  Symtuza SmPC

That’s right! Doravirine has minimal CYP450 interactions and would not interact with Amlodipine.

Amlodipine is metabolized by CYP3A4, so any strong CYP3A4 inhibitor or inducer can cause clinically significant interactions.

Cobicistat‑boosted regimens (e.g., Symtuza®, Genvoya®) are strong CYP3A4 inhibitors, which increase amlodipine levels and the risk of hypotension.

Nevirapine and etravirine are CYP3A4 inducers which are predicted to decrease exposure to amlodipine, thus requiring monitoring and potential dose adjustment

Doravirine does not inhibit or induce CYP3A4 and thus can be administered alongside calcium-channel blockers such as amlodipine.

References:
1. Delstrigo SmPC; 2. Symtuza SmPC; 3. Genvoya SmPC; 4. British National Formulary – Amlodipine Interactions – available at https://bnf.nice.org.uk/interactions/amlodipine (Accessed February 2026); 5. Courlet, P et al. European journal of clinical pharmacology vol. 77,7 (2021): 979-987. doi:10.1007/s00228-020-03060-2

That’s not correct. Doravirine has minimal CYP450 interactions and would not interact with Amlodipine.

Amlodipine is metabolized by CYP3A4, so any strong CYP3A4 inhibitor or inducer can cause clinically significant interactions.

Cobicistat‑boosted regimens (e.g., Symtuza®, Genvoya®) are strong CYP3A4 inhibitors, which increase amlodipine levels and the risk of hypotension.

Nevirapine and etravirine are CYP3A4 inducers which are predicted to decrease exposure to amlodipine, thus requiring monitoring and potential dose adjustment

Doravirine does not inhibit or induce CYP3A4 and thus can be administered alongside calcium-channel blockers such as amlodipine.

References:
1. Delstrigo SmPC; 2. Symtuza SmPC; 3. Genvoya SmPC; 4. British National Formulary – Amlodipine Interactions – available at https://bnf.nice.org.uk/interactions/amlodipine (Accessed February 2026); 5. Courlet, P et al. European journal of clinical pharmacology vol. 77,7 (2021): 979-987. doi:10.1007/s00228-020-03060-2

Thanks for completing our knowledge check!

You’ve learnt that doravirine can be used with a range of non-HIV medications but want to learn more about doravirine’s real world data? Watch our real-world data animations here: https://www.msdconnect.co.uk/products/doravirine/clinical-data/real-world-data/

Note: This knowledge check includes a selection of DDI’s related to HIV antiretroviral therapy and is not an exhaustive list and therefore we would always recommend consulting the SmPC before prescribing any products.